To see how she really feels about it.

Matt sighed in relief when he noticed his ability disappear from her affects window. He was about to ask her how she felt when his sister leaned forward and put his dick in her mouth. “What are you doing?” He asked as she bobbed her head sucking on his cock.

Lisa popped her brothers dick out of her mouth and sat up with a frown on her face. “Why doesn’t it taste like it did the first time I sucked on it?” She asked looking at Matt as she slowly stroked him with her hand.

Matt thought about just getting away from her but was afraid it might hurt her feelings. He thought about what she was asking before he said. “It probably tasted different due to one of the abilities I have. I turned it off earlier while you were sucking my dick the first time.”

Lisa looked at the pen in Matt’s hand and asked. “Did you get these powers from that pen and can you turn that ability back on so I can taste it again?”

Matt was thrown off by his sister’s blunt request to suck his dick. “Why do you want to taste it again?” Matt asked as he examined her a little more closely.

Lisa stopped stroking his dick and looked thoughtful for a minute before she said. “When you made it so I can ignore how you have changed I decided to see what I wanted. When I could look at you without feeling like I was losing my mind I realized that even though you are my brother I still wanted to fool around.” She blushed a little and looked away a little embarrassed. ‘You wanted to try this.’ She told herself and she shook her head and looking back at her brother asked. “If it’s ok with you I want to try some thing we shouldn’t do as siblings?”

Matt could see his sister was very serious about what she was proposing. He knew this was a line that once they crossed it there would be no going back. Looking at his sister he said.