So I had this idea
Being transmigrated into Ken Tanaka's body a year or two before plot.
With a self-discipline system or heaven rewards diligence golden finger.
He will improve his looks, life, maybe become principal and improve the school. Some business on the side to become rich. Write songs?
A cool mentor to Glee students.
Sleeps with the hot female visitors to Glee.Some friends with benefits. Maybe even with Glee girls once graduated