What does cinch

Yep! It’s gonna be a cinch! mean?

“The Northern dragon tribe is one of the most vicious tribes,” Firy said. “Even if your things got stolen, I can’t risk the safety of my team members by sending them to get them back, because you might not get them back, and the WB might lose a member—permanently.”

***
“I’ll go.”

Silence fell, and all peple present turned their stare toward Rose.

***

“I told you, I can’t allow it,” Firy repeated, stern and imposing. “I can’t let civilians risk their lives like that. I’m sorry, but you don’t have what it takes.”

“Sure they do!” Rain exclaimed, flying up into the air and putting her goggles on. “’Cause I’m going with them!”

“You are?” Rose and Firy asked in unison.

“Yep! It’s gonna be a cinch!” the garpy continued. She turned to the people, waving them off. “There you go! You’re gonna have all your stuff back tomorrow!”