Juku Ren has short light brown hair. His bangs sweep off to his right side. A chunk of hair on the left side of his head is sticking up. Another chunk, more closer to his ear, is pointing down. His eyes are a similar shade of brown. He has fair skin. He has a Martial Arts Club headband. Sometimes, he can be seen with cross-eyes.
He wears the default school uniform unless customized.
Among all the personas currently implemented in the game, Juku is a Teacher's Pet. Meaning that he will run and tell his favourite teacher about what he had seen when witnessing murder. He doesn't have the animations to react to a camera pointing at him yet.
At 7:05 AM each day, Juku will enter the school ground fifth in line on the left to school. He walks to his locker at 7:10 AM. At 7:15 AM, he will walk to the Martial Arts Club on the second floor.
At 8:00 AM Juku will walk into classroom 1-2 and sit in his desk. He will start class at 8:30 AM, and will leave to go back to the Martial Arts Club at 1:00 PM.
Juku will walk to class again at 1:30 PM and finish his afternoon classes at 3:30 PM. Afterwards, he will head to the Martial Arts Club and will stay there until the end of the day. If the player joins in club activities, he will practice kicking with the other members from 5:30 PM to 6:00 PM.
If the Martial Arts Club is inactive, he will socialize with the other former members outside of the club during periods when he would normally attend the club (7:15 AM, 1:00 PM, and 3:30 PM).
- He is an apprentice-level disciple of Budo Masuta, as it is said in his Student Profile.
- He was implemented in the November 15th, 2015 Build.
- His name is a play on words. "Jukuren" (熟練) in Japanese can mean either "skilled" or "proficient", however this does not reflect Juku's strength level, which is "very weak".
- Juku may or may not remain in the game for he is not a true character and just a test dummy for debugging. If he does remain, he may undergo a heavy change.
- On the January 1st, 2016 Build, his persona changed from Heroic to Teacher's Pet.
- He is the only student in the Martial Arts Club who does not have the Heroic persona.