Zenryousei Ginsei Gakuen Monogatari
There so many cute couples!!! Atsuya(the master) and his adorable lover, Kyousuke(servant) are great together. Takamori(the tall student) and Nakatani(sensei) are amazing. Takamori's childhood friend Miyako(small student) and Ayusawa are a ADORABLE COUPLE!!!!! But, my favorite couple of all times are kurafuji(the security guard) and the art teacher Ooga.
Yogoto Nayamashii Niwa De
This manga is so good. I definitely love Himuro and Yumihiko relationship. Yumihiko had a hard time for his family until a theif change his life. It turn out Himuro is a thief, nickname Caesar. Also, he deeply in love with Yumihiko when he first met him. Miyajima (the boss of gigolo club "million dollars") is really handsome and his lover Yukinari is good looking, but need to control his hot-temper. Their relationship great, but there were a lot of problems, but in the end everything went alright.
Goshujinsama wa Ouji ga o Suki
Kowarekake No Omocha