There's no school, and no teachers; there's one NPC, and the rest are "vacationers". There's no Story. You don't have any stats, and don't have to build up your "club". You'll wander around and find "topics"; if a girl mentions a topic and you have a matching topic, you'll rank up your friendship. You'll also get topics by going on "adventures", doing crafts, having meals (no minigames), etc. Eventually, you'll get "frisky". Rinse, repeat. Fairly new; addons are still being ported over (cards will transfer, but their outfits will be buggered up, as the "outfit slots" are in different places), but a lot of the major ones (cheats, translation, pregnancy, added positions, etc.) are included.
And, yes, this is ScrewThisNoise's repack.