いっ はつ いちゃう
i' hatsu nuichau

Godan Verb (ku)
Godan Verb (u)

The completive aspect (contracted form) - indicates completion or regret of 一発抜く

1. I'll pull it off in one go.; I'll just do it quickly.; I'll take care of it immediately.; I'll do it without hesitation.

Completed Action
Colloquial