He took her enthusaism for further permission. The doctor began pushing her backwards, towards the large bed that nearly dominated the room. Sinister giving a pleased 'mmm' at the feel of her nails digging in. So possessively, like she could actually mark him as hers, so like Malice.
His mouth moved to her earlobe, sucking lightly as let his teeth graze and nip just a enough to make her shiver. The hand on her back lifted higher, fingers toying with her bra strap. And that hand on her neck? It slipped lower in a caress that fully intended to end with cupping one breast and giving a squeeze.
Sinister was almost excited by the current situation. Not because the girl was nearly untouchable by others. But because she was once again giving into her darker side. The side that happily called herself an 'evil' mutant under Mystique's guidance and only left because she was desperate. Not because she was a 'good' person. Because she was scared of losing control.
Whether she let him go all the way or not, tonight would offer a most pleasing out come. He already had what he really wanted from her. All he need do now was continue to encourage it.