Although Agari looks scary, he is actually very shy and hides underneath the water with only his fin visible. Agari is too nervous to speak because he ends up scaring people when he opens his mouth and flashes his many sharp teeth, so he uses body language to communicate instead. However, when he talks, it's show that he has a very deep voice.
It's rumored that Agari was the model for the movie Jaws.
- He is referred to as "senpai" (an older person, usually of higher rank or just deeply respected by the person using this term) by Wakasa because sharks are the top among the fish.
- He used to sing and judges the other characters singing on karaoke night.
- He gets along really well with Maki.
- He hates stripes.
- He and Tatsumi are able to understand each other using body language.
- He often comforts Wakasa.
- Once told Wakasa to kiss Tatsumi after they had a fight.
- He is a weak drinker.
- He once gave Tatsumi the middle finger (he thought it was a compliment).
- He has the need to constantly shed teeth, as new ones keep growing.
- His name is a pun on the japanese word for "stage fright".