He also appears in Extra Chapter 4, where he and Tomohiro are playing a dating sim while Masato cleans up the student council room.
Throughout this chapter, Tomohiro is still feeling the after affects of losing Ryosuke as he's brought up many times, Yoshiki manages to calm Tomohiro down through those.
After Tomohiro takes out his DS it starts picking options by itself, ones Tomohiro says Ryosuke would pick and then the ghosts show up.
Since he's been hanging around, Mitsuki Yamamoto started ordering him to do student council chores.
He appears in Extra Preview and plays the same role as he does in Chapter "Tooth" from Corpse Party: Book of Shadows. When the tag is picked up, his spirit can be heard calling out Kizami.
When it seems the two can't escape, the DS plays a tune that brings them over allowing them to escape, Tomohiro would believe that to be Ryosuke helping them.