Dirty way to destroy the goddess's hero, vol. 2 (light novel - Sakuma Sasaki

After defeating the heroes, Shinichi is ready to live out his happily-ever-after--until a powerful spell blasts through the sky, aiming for the Demon King and marking the arrival of their newest enemy, the Saint! When Shinichi realizes she won't fall for his sweet nothings, he scrambles to come up with another plan, which now involves Rino's debut.

as an idol!?.