High school student Hana Yamada's lover is the school's nurse... but Shuuji Kidou-sensei is a mean and disgusting person. They can't tell anyone about their relationship, but he satisfies her heart and body, so Hana is very happy.
She soon starts feeling uneasy, however, because he keeps falling for other girl's sex appeal and keeps hiding things about himself. As if that weren't enough, a man who looks like Kidou steals her lips after saying "I don't care if I'm just his replacement, let me be with you"...?!