Digger was just barely coming to the realization that he might be bi-curious, which definitely lent itself to Greed coming into his life. He wasn't sure if it was really just Greed all together or if there was something else underlining there he'd never worked out.
"Oh not really, I'll leave it at looking for right now." Because he really didn't know..."I like girls mostly..." One's that didn't want to sock him in the gut and make him feel worthless. Sloth had done that and his last girlfriend had kind of treated him like an ass. Maybe he just wasn't boyfriend material. He was the guy all the girls wanted to be friends with tho.