You seduced her

"Yes, it's not bad at all. I like the space, even though I don't have enough furniture to fill it properly."
You looked around and nodded, "Well, I do like what you did with it." Then you turned towards her, "I wanted to ask you, what do you think about this psychophysical stuff?"
She briefly lifted an eyebrow, "Why? It makes sense, doesn't it? Most reactions to something which might seem psychological are physical as well."
"Yes, of course, but why would reactions to strangers be stronger in some cases than with someone you know well? You'd think it would be the other way round," you said then took a sip from your coke.
She shrugged, "Familiarity does make a lot of things more comfortable." She paused for a moment then added, "Like when we talked at the cinema. That probably wouldn't have happened that way if we were total strangers."
"Yes, sure, but that's something different from the hugging examples the professor made. Talking isn't exactly something physical." You placed a hand on her thigh, "This must have a different reaction than just talking."
Her thigh tensed up briefly under your hand. "Yes, of course that's different, but that doesn't mean there is a psychophysical reaction."
You pressed with your fingertips slightly onto her inner thigh, while you felt your member stiffening slightly. "No? I felt your muscles tense for a moment, that's not related to something psychological?"
She nodded, "Well, yes, it is, but you could say that almost everything is somehow related to something psychological."
You had slowly moved your hand a little towards her crotch while she spoke. You nodded and replied, "Okay, but not everything psychological has a physical reaction. I'm sure this has some physical reaction." She hadn't moved your hand away, so you moved it up her thigh a little further almost touching her crotch now.
She blushed slightly and nodded, "Yes, of course it does. But I'm not sure if that's a psychophysical reaction." She bent forward to place her glass on the coffee table and you took the opportunity to slip a finger against her crotch.
"Okay, so when would it be psychophysical?" You pressed your finger against her crotch, "This?"
She closed her eyes for a second, then shook her head, while placing her hand on top of yours, "No, that's still a physical reaction. It would be psychophysical if we were talking about how your finger is pressing against my crotch some other time and it evokes a physical response in me."
"But that's not like the hugging examples the professor gave us," you objected.
She nodded, "I agree, but this doesn't release any endorphins, as far as I know. It's just a physical reaction to something physical."
You moved your finger against her crotch under her hand, "So you're saying that this doesn't make you feel good?"
She pressed her thighs together and shook her head, "It's not the same." She pulled your hand from her thigh and stood up, "Come on, stand up."

You did as she asked and stood up. She surprised you when she suddenly hugged you tightly and you wrapped your arms around her.
"Tell me this feels different from having your hand on my thigh," she whispered.
You nodded, "Yes, of course it does. It's different and very nice too."
"Okay, different in what way?"
You hesitated for a moment while looking into her eyes, then offered "Softer?"
She chuckled, "I think you mean gentler?"
You nodded then kissed her on her lips and moved one hand behind her head, caressing her through her hair and over her back with the other. After a moment she started to kiss you back and began to move one of her hands over your back. Slowly you parted your lips and pressed the tip of your tongue against her lips. Suddenly she pulled her lips back and looked at you.
"I don't think this is a good idea," she said.
"Why not? Did it feel bad in any way?" you asked with feigned innocence.
She shook her head, "No, it didn't. It still doesn't make it a good idea."
"Come on, you can't blame for it. You're an amazing woman, I wanted to kiss you ever since I first saw you. It's just a kiss." You pulled her tighter against you and leaned in to kiss her again.
She didn't pull back and kissed you back for a moment, then broke the kiss and shook her head. You traced with your fingertips along her neck, then kissed her neck on the opposite side before murmuring soft, "I bet it does feel great."
She tilted her head with a sigh, "Yes, it does, but..." You continued to kiss along her jaw while she spoke then ended up on her lips and silenced her. She kissed you back and while you caressed her slowly you traced her lips with the tip of your tongue until she parted them. Gently you caressed her tongue with the tip of yours and she began to move hers over yours. One of your hands moved over her back onto her buttock and gently squeezed it. It caused her to press her hips against you, stiffening your member further. You moved your hand from her neck to her side and began to caress the side of her breast, slowly bringing your fingertips towards her nipple. You felt it stiffen under your fingertips and as you increased the pressure a little she moaned softly in the kiss. With slow firm circles of your fingertips you made her moan again, then she broke the kiss, pulled out of the hug and sat down on the couch breathing heavily.

"What's wrong?" you asked.
She grabbed her glass and took a big sip. "I can't," she said.
"Why? Do you have a boyfriend?" you asked, knowing from her Lifelink she didn't.
She shook her head, "I don't, but I just can't. Okay?"
You shook your head, "I don't understand. Why not?"
She took another sip from her drink, then placed the glass on the coffee table. She took a deep breath before facing you, "I don't want to get to the point of no return. Let's keep it at that."
"What do you mean by the point of no return?"
She sighed, "Sex."
You looked puzzled at her, "What's wrong about having sex?" You placed your hand on her thigh again, "It didn't feel good what we did?"
She shook her head, "No, it's not that. It's... Well... we simply can't have sex. I had to stop before it's too late. I'm sorry."
You moved your fingertips towards her crotch while she spoke and felt the heat radiating from it. You gently squeezed her inner thigh, "It's okay, Lisa. We can enjoy each other anyway, can't we?"
She shook her head, "It's not that simple."

She took a slow deep breath while she seemed to seek for words. You seized the moment and kissed her again, pressing her back on the couch. She didn't kiss you back at first, then as you moved your hand onto her breast and gently kneaded it, she did kiss you back with a soft moan. You moved the fingers of your other hand against her crotch, rubbing it along the seam. Another soft moan escaped through her nose. You moved your hand off her breast and tugged at her polo shirt, then moved your hand underneath it over her soft skin and sought her nipple. She tried to shake her head in the kiss, until you pressed your fingers firmly against her entrance through her jeans, causing her to moan a little louder and jerking her hips. While deepening the kiss you stroked her crotch up towards her clit and back. Her breathing became heavier and you removed your hand from her breast to undo the button of her jeans, quickly lowered the zippper and slipped your hand inside her panties. Your fingertip slipped between her folds, enticing another moan from her. Then dragged her moist up to her clit and began to massage it. Her fingertips pressed into your shoulders as she moaned and gently rocked her hips. You felt your member press firmly against the tightness of your own jeans, eager to get out and into her. You continued to massage her clit in the same pace as your tongue moved over hers and it didn't take long for her hips to move urging against your finger. You dipped two fingers between her folds and pressed into her entrance, then rubbed in and out of her. Her moans and breathing increased and she broke the kiss to get more air. You slowed down your pace, dragged a fingertip back to her clit and paused.

She shuddered and shook her head, "Noooo, don't stop now."
You grinned and started to massage her clit again, "Oh, now you don't want me to stop. See? You do like it."
She moaned and opened her eyes, then looked at you, "I didn't say I don't like it."
"Let me make it a little better for you, then," you said as you tugged on her jeans, pulling them off her hips and taking them off along with her shoes.
You climbed between her legs again and slipped your fingers into her inside her panties, then dragged them back onto her clit, which caused her to jerk her hips up with a longing moan. While leaning on your elbow you brought your other fingertips back onto her nipple and kissed her again on her neck. You felt her moving rhythmically underneath you and you matched the pace of your fingertips on her clit with hers. It didn't take very long before you felt her hips begin to shudder and her moans to increase in pitch and loudness. She pressed her head back and moved her hips faster under your fingers. You tried to match her pace and then suddenly her body began to ripple underneath you. You slipped two fingers into her entrance and felt her tightening and relaxing on your fingers. She gripped your hand through her jeans and pushed it into her while she arched her back and shuddered. She held your fingers inside her while the shuddering slowly subsided and finally let go.

Her body slowly relaxed and she looked at you while still breathing heavily. "I guess it's my turn now," she whispered and reached for the bulge in your pants.
You smiled and nodded, "Yes, I'd like that!"

She unbuttoned your jeans, lowered the zipper and slipped her hand inside your underpants. Her warm fingers enveloped your stiff member and she began to stroke along its length. After a little while she removed her hand, spit in it and brought it back, then increased the pressure and strokes, causing you to moan and rock your hips.