Oujisama Ni Narenai summary:

Because of his looks, Seiichi was treated as the "School Prince" whom everyone adored. Since he didn't want the girls to be disappointed he decided to act the part. To conceal his true nature, he made sure to politely reject all the girls' confessions. But then one day, some random boy suddenly confesses his love for him, will he still be the gentle prince everyone's in love with?