PLEASE recommend an emotional, beautiful student/teacher yuri romance! Even shoujo-ai is okay... Even ecchi is okay... Even just implied subtext is okay... Even hentai is okay... 🤣

Key thing should be emphasis on emotions.

The more forbidden, the better.

I also wouldn't mind any other lesbian romances featuring a significant age-gap (> 5 years).

Recommend, please?

Pure Water Adolescence
"Bruges" (the prequel to Applause)
When She Touches Me
The Structural Formula of First Love
"20-Year-Old Girl x 30-Year-Old Maiden" and it sequels (printed in The Conditions For Paradise and A Lapis-Lazuli Blue Dream; there is another age-gap romance in that second one, "Nostalgia"), though it doesn't really go into the "forbidden love" aspect
There's a teacher-student romance in Hanjuku Joshi (though they're not the main couple of the series), and an age-gap romance in its sidestory "Hanjuku Fujoshi"
Chatting at the Amber Teahouse, though it's more sweet than "forbidden"
Our Fake Relationship
Hatsukoi Shimai has a teacher-student romance but they are side characters

Witch (Chi-ran), Sweet Lovin' Baby, and I Fell in Love For the First Time have some of the elements you asked for, but I don't know if they're quite what you're looking for.

try searching Yuri Hime Wildrose i think there are some story about it there ^_^

Seconding: Junsui Adolescence

try Cotton and Two and Two

Quote from HiddenSideQuest

try Cotton and Two and Two

Sorry, I don't have a suggestion - but I wanted to let you know; Cotton is NOT yuri - or even shoujo-ai. It's simply about a very close, non-romantic relationship between a difficult teenager and her rather immature sister-in-law. The older woman gets married (to a guy) at the end. So I don't think it fits at all here. But if you're satisfied with almost unnoticeable one-sided subtext (on the part of the teenager), give it a shot. It's a nice story, but not something you should read for the GL (which doesn't exist anyway ^^).

I LOVE YOU, MIZUNO_YOUKO. Btw, are you involved in the LJ yuri community? I feel I've seen your name before... 🙂

Thanks also to everyone else, and to calstine for the clarification! I'll take the subtext, lol. 😀

I'm glad you found the suggestions useful! Yes, I have an LJ under this same nick.

Weeell, extremely subtle shoujo-ai is kind of Konno Kita's thing. Cotton's even more subtle than The Secret Stairs most of the time, but it is intended to be seen as shoujo-ai, and there is a scene involving bathing and breast-fondling.

As for the request, all I can think of is Strawberry Strawberry Strawberry, which is hardly the kind of thing you're looking for. The rest has been recced by the venerable mizuno_youko!

I especially like "Bruges". It's definitely emotional, full of forbidden love, and beautiful.