Panel 1 gives him access to a Piercing Fire AOE that does not cost MP, very useful against MP denial teams.
Cons
Having no innate ST skills means he will be walled by Drain Teams. It is recommended to pair him with demons like Alice to eliminate Phys Anti-Pierce demons that prevent him from sweeping.
No natural Pierce outside Panel 2 might cause issues when out of MP.
Notes
Limited-time Collaboration unit. Nobody knows if he will be rerun.