Sure. The Ouran Host Club manga has finished. It had a proper conclusion that covered all the important aspects and left a lasting impression on readers.
Well, there could be a love story between Kyoya and a new girl who joins the school. The girl is a bit of an enigma. Kyoya, always the calculating one, tries to figure her out for the sake of the Host Club's business. But as he digs deeper, he discovers her real charm. She challenges his cold - hearted business - like approach to things. They start having little debates and gradually, Kyoya finds himself looking forward to seeing her every day. His feelings grow from mere curiosity to love, and she also starts to see the warm - hearted person beneath Kyoya's calculating exterior.
The male OC could be an undercover journalist. He joins the host club to expose the so - called 'extravagant lifestyle' of the rich students. As he spends more time in the club, he starts to understand the real personalities behind the hosts and realizes that there's more to them than just their wealthy facades. This could lead to a story full of self - discovery and unexpected friendships.
One idea could be an OC who is a new transfer student at Ouran. She's a bit of a tomboy and accidentally stumbles into the Host Club room while looking for the library. The Host Club members are intrigued by her unique style and she ends up becoming a regular visitor, slowly forming a special bond with Tamaki. She could introduce them to new hobbies like skateboarding.