Angelo's Stand ability was brought forth by the mysterious bow and arrow, and apparently they're also connected to DIO. After defeating Angelo, Jotaro thought that the danger had left the city, and tries to find the whereabouts of the bow and arrow. A few days later, Koichi is walking home with Josuke, and they pass a house that should be empty...
Yeah... The guy in the school 
uniform might be our new enemy.
نعم... قد يكون الرّجُل ذو الزيّ المدرسي
عدوّنا الجديد
Ja … Der Typ in der Schuluniform
könnte unser nächster Feind sein.
Sí. El hombre del uniforme escolar
podría ser un nuevo enemigo…
Sí. El hombre del uniforme escolar
podría ser un nuevo enemigo…
Oui, c’est peut-être
un nouvel ennemi,
Esatto... L'uomo con l'uniforme scolastica
potrebbe essere un nuovo nemico.
Sim. Esse homem do uniforme
pode vir a ser um novo oponente.