Uhm... What? No! >=[ Volke is socially and emotionally underdeveloped. Although 26, she never had the chance to be a child. Not really. She never really had the chance to be a teen. She did have the chance to be normal after 'The End of The Night,' but she didn't even know-rather, have a clue how to until 10 years later! She's only now, rather, in the past year or so before the events going on in-game, really learning how to... not be a cold, emotionless killing machine. Considering the backstory I have set up for her.... .... .... that I didn't tell anyone about. Whoop. Shouldn't have gotten mad. ^.^;;
Anyway, she's/he's, until recently, been emulating a normal person's life... sometimes. However, she couldn't really understand it until recently. The way people could display their emotions, that is. No personal experience of her own. So.. when stuff like that happens, she emulates what she sees others do. In this case, kissing.
... although, she really did get super happy. She actually transforms while eating because of how happy it makes her. ^.^
EDIT: She also didn't understand how people could feel so strongly about things, even when he/she did him/herself once or twice throughout his/her life.