Colorful Line
Complete | Ichikawa Kei | 2000 released
2020-05-13 08:29 marked
https://www.mangaupdates.com/series/25cn1dc/colorful-line
Concierge No Koibito
Complete | takagi ryou, Takagi Ryo | 2013 released
2023-08-24 18:23 marked
This isn't a oneshot. There's a full volume. Chapters: 1. Concierge no Koibito 2. Wakadanna no Koibito 3. Shachou no Koibito 4. Bishokuka no Koibito 5. Shodouka no Koibito. I've only read the first chapter available.
Confession Game
Complete | kojima mihoko | 2005 released
2023-10-10 13:50 marked
https://www.mangaupdates.com/series/73ehkg9/kokuhaku-gokko
Shinshunki Miman Okotowari
Complete | Watase Yuu | 1991 released
2023-10-10 18:36 marked
https://www.mangaupdates.com/series/t5vr9sr/shinshunki-miman-okotowari
Crazy Love Game
Complete | Nanajima Kana | 2007 released
Cubism Love
Complete | shibamura yuri | 2010 released
2023-10-14 13:59 marked
https://www.mangaupdates.com/series/4ajrhru/cubism-love
Cyboy
Complete | NISHIKATA Mai | 2008 released
2023-10-14 15:46 marked
https://www.mangaupdates.com/series/rgr5seh/cyboy?method=time_added&perpage=25
Daiji na Koto na no de, Nido.
Complete | KUROIWA Chihaya | 2014 released
2022-03-22 06:16 marked
https://www.mangaupdates.com/series/5zss2pc/daiji-na-koto-na-node-nido https://ridibooks.com/v2/Detail?id=1016003829
The White King
Complete | Nagabe | 2000 released
2023-12-21 20:02 marked
Chapter 5 of Nagabe Tanpenshuu Henteko na Ai (Love on the Other Side).
Cinderella Tokkyuu