Vaginally and use a super power.

"I have to have that inside me...I need it now." She says as she pushes you onto your back, “Don’t worry though, I’ll make sure we both enjoy it.”

She removes her pants and throws them across the room as she slides to straddle over your cock. She gives you a dirty smile as she slowly lowers herself and guides your cock into her slit.

“Ooh… I can feel it going deeper. It’s piercing into me… is this why they call you Lancer?” She says with an erotic giggle.

“No, I don’t know why they call me that. I always thought ‘Omni’, as in omnipresent, was a more fitting name. It sounds a little girly though…”

Terra looks at you confused. While your little description was vague, she seems more upset that you aren’t as aroused as her.

“You can tell me your life story after we’re done… right now we….” She remarks hostilely.

“I just thought you should know… that way you wouldn’t be too surprised.”

“What are you talking….Uh… ooh! Umm.”

One of your powers involves the ability to project a semi-corporeal form of yourself which can perform actions somewhere remotely while allowing you to still act normally in your visible body. In essence, while you are only seen in one spot since you feel like you are in both spots you can act or be in two locations at once.

Terra seems completely caught off guard when you create your invisible double. She probably wouldn’t even have known it was there if you hadn’t decided to mount her from behind and slowly insert your mimic cock into her ass. She seems so surprised in fact that you can feel her pussy contract around your member and shutter in orgasm.

When your second cock presses its entire length into her ass and her body finally relaxes she looks at you with an ecstatic smile.

“Being able to be in two places at once means we can have a threesome with just the two of us. I hope you don’t mind?” You say with a wicked smile.