SutoSuto: Stalker ga Stalker Sareteru Hanashi - Vol. 1 Ch. 0 - Characters

[MangaDex]

 

[IrregularPerson]

looking at the different hearts in their relationship chart. and giving this a reread. all of them have aspects that is stalker-like, such as mirroring material possessions, investigative research, but their love is different:
one is obsessive idolatry without reciprocity, one of closeted love, and one is dense and jealous.