Bucky has been through more shit than anyone should ever have to go through and he has to carry it with him as a weight every day of his life. He doesn't want to carry it in here, though, so he kicks off his pants and draws up close to Karen and, by extension, the bed.

Let me kiss you again?

Bucky likes kissing and not just a prelude to other things and he hopes Karen will indulge it from him.