Crossover Specialist

(with Koichi being the only character from the previous part to show up)

Even though this comment is a couple months old I felt I needed to address this. No offense, but your dislike for the character has clouded your memory. Jotaro was NOT lazy in Part 4 and he didn't 'order everyone to find the killer while he did nothing'. When the Morioh gang discovered Shigechi had died and his killer was a stand user, everyone decided to be on the lookout and get involved. Jotaro took Kira's button and started going around investigating who the killer's identity was. Following that, he and the gang went to Kira's house for more research in the Atom Heart Father chapter, and helped in bringing him down in the final chapters.If you're talking about why he wasn't around between Atom Heart Father and the final chapters, remember that DIU is about Josuke and his gang. Jotaro had his time in the spotlight in Stardust Crusaders. Surviving Joestars/Characters from previous parts take a backseat for the new guys. It happened to Josuke in Vento Aureo, and Giorno in Stone Ocean. Also, during his stay in Morioh he was working on his thesis on starfish.