[grandchaosSR]

Originally Posted by Sumeragi

It's been gone over in the Ai episode thread, but no. Junichi does not have the guts, nor the girls that loose a personality, to be making love while still going to high school. I mean, jeez, why do people assuming acts would be done as if it's natural?

Premarital sex is pretty normal in this modern times. Anyway I said "probably" in Ai's case. In Haruka's case the writers followed her Best Ending in the game. This is from her MAL profile

Spoiler for game:

Best End: Morishima reserves a hotel room on the pretext that Tachibana will be meeting her parents. Her parents aren't there. She takes a shower and comes out in a towel. She's flustered about Tachibana not peeping or why he hasn't confessed again despite having confessed twice (and getting shot down both times). She tells him that she's so in love with him that she can't think straight anymore. Tachibana smiles and tells her that the clumsy senpai he got to know is the senpai he fell in love with. Morishima tells him to call her Haruka and they share a passionate kiss, while her towel falls off. Sex is strongly implied. A few years later, Tachibana becomes a police detective and Morishima is his loving waifu. (Anime end)

So its safe to assume that something happened.

Sheesh this is just a show. There is no need to get serious.