PoliPro!: 23-sai Gakeppuchi Idol Kouhosei ga 3-dome no Shoujikide Debut Mezashimasu!!

Kureha Tamaki is told by his talent agency manager that he doesn't have what it takes to be an idol and is offered a sales position instead. He decides to try his luck with other agencies but is met with rejection after rejection. Desperate for another chance, Kureha applies to an audition at Polish Productions, a new agency he's never heard of. On the day of the audition, he shows up at a shady building with no one else around. He nervously rings the agency's doorbell and is greeted by a tough and scary-looking guy with scars on his face...! This is the story of a young but late-blooming idol trying to make his debut with his fellow charismatic trainees! (Source: MangaPlaza)