As for Agil, yeah, could go either way, maybe he's there to give Suguha more free time, or he will hit on her.Exactly, this is the "some reasons" I was talking about, hence "bigger dick". She clearly expects Kirito to be as endowed as Inoda (while I believe she never saw it). This is the starting point of a later twist.
As for Suguha, for sure she is in love with Kirito, but Hebeshima already went pretty far with her, and I wouldn't be so sure she sticks with Kirito. I mean in the last update, just after the diner with her, she says she will go to Kirito's appatment but has something to do beforehand (while blushing). Smells like Hebeshima's influence.
And then you have Agil... (I might be wrong, but I think this is the first time he appears in the game). I guess the dev is preparing some bbc actions for Suguha or any other female characters.
As for Hebeshima, well, she is OK fucking him, but on her terms and she is currently turning into an obssesed yandare, so I guess she will Go for Kirito for now.