He probably goes home & tells his wife assorted stories about all the girls with obvious crushes on him. Then he & his wife play games about what what daft thing the Crush-holder will do next, and the wife comes up with more and more creative ways she'll punish him if he's even remotely tempted.
Yes I have known a few lecturers who do exactly this.
To my knowledge I'm fairly sure I've done nothing suspicious as it were!! I actually barely speak to him aside from the odd meeting about my dissertation.
It's not like I'm expecting anything to happen, and it's mainly his passion for his subject that interests me - he's certainly not the tutor most of the students would go for, most of the others are terrified of him, lol.