Yes, you can also get Lester as an option (though his relationship stats were bugged for a bit, so maybe you missed out on some points). Then again, I think getting all five at the same time is really difficult, so if you got four of them, that's already an accomplishment.
I'm guessing you'd have to choose to hang out with Lester during one of the moments you're given an option to if you want to get enough points with him. As for getting the others, I'm just nice to everyone. Some might say I'm too nice (and in fact Az'Lean did say I'm too nice when setting up the barriers).