Is Our Teacher Really The Bottom?

The narcissistic high school teacher Mamoru Hizaki has a thorn in his side: his handsome young colleague Junichi Namiki, who has been stealing the spotlight ever since he came to Mamoru's school. When the faculty go out drinking one night, Mamoru sees his chance to get revenge. He is going to drink Junichi under the table and show him who rules the roost. However, things don't go exactly as planned, when it turns out Junichi is not quite as mild-mannered as he appears...

(Source: Renta!)