Almost finished my first round and I wanted to ask about an H-Scene I may be missing. It's the 2nd one in the right column under Kohakuren in the replay list. Is it NG+ only? It just seems kind of weird for that to be the case given it's placement. Thanks to anyone who can answer.

If I'm not mistaken, it's the hot springs scene with Aht and Kohakuren. Level them both, and install the hot springs.

Ah, so that's it. I actually kind of expected the contents of the scene since I cleared the bonus stages but, didn't think of installing the hot spring. It also didn't help that I missed the shop with its recipe entirely. While we're at it, are there any other scenes, H or otherwise, that you need certain furniture for?

There are other scenes that are triggered by furniture, but they are mostly very short and not important. You can find the list (search for "kamidori poster").
Hot springs have several other "important" events - scenes for Uya/Crayl and Melo/Eliza (maybe Crayl/Crayanne too) give them new skills, and ones with Lyphia/Evelyn and Asmodeus are required for their quests (although they are both NG+ only).

note: hot spring will be toword the 250 sense .... but in the end ng+ item will give more sense then hot spring and ramen shop ( u need it for ng+ character anyway)