Kind of bugs me that the MC isn't forthright about "Oh, and I'm banging blondie... and mom. And all of little sis' friends" with either of them. I can understand the reluctance with Bella, but not so much the redhead, what with her being the more accepting of the idea.
I understand the timing isn't ideal, but I can only imagine the fallout if that gets discovered later on that he'd lied to them about even more.
Edit: And playing a bit more along the "honesty" route, and holy damn did I NOT expect her to take that kind of initiative with the oldest sister! Can't remember their default names, so I'm using hair colors or age as reference