[Jotaku]

Use it to heal yourself by knocking down chasing enemy with ranged attack lol
It worked against Trap in Kaneki sometimes so it will probably work sometimes.

I don't see its particular use in offensive action because its ranged attack damage is so low and also knocking down makes enemy temporarily un-vulnerable.

CCG Tanker build worked better with Ukaku than Ukaku because it has to have a way to survive when HP is too low as it is tanking build. Ukaku didn't make me successfully run away from Trap when my HP was small, but Ukaku allowed me run away and heal a lot easier against him.

The only possible way to make damage with Ukaku I guess is just skill spam or special move.
But, I haven't thought that much details yet about how to make damage with Ukaku, anyways.