2 - Head to the Children's Park
"First, I'll gather some info at the scene of the crime. If I ask around about the bag, maybe I'll find some clues."
Head to the location on the map. It's in the north west of the map. It's where you can enter the sewers to get to the doctor.
Talk to the people.
The two homeless people like to have 2 Bento's.
Go over to the Poppo Shop and buy 2 Tonkatsu Bento Lunch Sets.
Go back to the Park and hand over the Bentos
3 - Find the Thieves
"I should find somewhere that young guys might hang out. Maybe some friends would have an idea, too."
Head to the Yoshida Batting Center.
Inside, talk to the group.
After finishing, talk to them again. This time, select the "About the Bag being Yellow" option.
After, you enter Active Search Mode. Investigate the Yellow Wristwatch.
Then stop the investigation.
In the conversation, say "The Owners initials are carved into the dial".
Defeat the thugs.
4 - Head to the Champion District
"The bag was tossed in the garbage in the Champion District. Guess I'll go look."
Head to the location on the map.
The bag is lying there in the alley. But it's empty.
Find the homeless man. You see where it is on the map - it's a blue folder sign.
He's wearing the jacket.
The nicest thing to do now, head to the "Don Quijote" Shop in the south of the map and buy "Warm Clothes" for him.
Head back to the guy and give him the warm clothes.