hare of inaba

[day]

So should I just let this thing sit in my stock until its maxed? It's 10 levels above me and kinda useless but at max he'll have zero weaknesses. pretty funny

[Penguin Lord]

Register to compendium if you don’t need it now.
It’s not useless though. It can learn a lot of resistances to pass to another demon during fusion or create a supporting demon out of it instead of using it as a damage dealer.
But with so many options, if it doesn’t appeal to you just fuse it and move on.

[Arifufu]

same as above, register it to compendium

later in endgame you can buy grimoire as many as you want and you can level up it to the max in no time