An unhealthy obsession with another man, bordering on homosexuality, characterized by sporadic mantasies and insistence on regular mandates.
M1: Do you think its odd that Tim is always with Eric? They eat together, watch tv together, study together and even go out together, and he just put up a life size poster of the two of them in his room.
M2: Yeah, sounds like its bordering on manfatuation to me...
The unhealthy admiration a man exhibits when referring to the achievements of his favorite sports figure.
"Unaware of my own manfatuation, I found myself marveling at Kelly Slater's naked competitiveness."