Recommend good Ultra Rare characters to beat the 'Mae Mae' boss...

Horororok! Teacher Meme has the 'flying' attribute, so Ultra Rare units with the 'anti-flying' trait, like the wind god Windy, are very effective. As the saying goes, 'Know yourself and your enemy, and you will win every battle,' so don't forget to constantly produce meat shields to maintain the frontline. Hmph!

It's hard to recommend without knowing which characters you have, but you could use your Ultra Rare units that counter flying or non-elemental enemies. Maintain the frontline with Cat and Wall Cat, supplement damage with spammable dealers like Cat Enma, and add debuffers like Cat Wizard.

Looking for CC or long-range characters (not bulky DPS like Golem).

Take the monk.