Quote Originally Posted by Ryllharu View Post
Okay, I guess you didn't get it then.

That is the OP. Mushoku Tensei and ARIA both use the opening theme song set over added unvoiced runtime to set the tone of a given episode before it actually starts proper. It's just a technique so rarely used that people assume the series doesn't have an OP.
I coulda sworn MT S1 had a real OP...it just only showed up in, like, 1 episode.