Suguru after his passing from the events of the night parade of a hundred demons, found himself turned into a vengeful spirit after his body wasn't properly disposed of by Satoru Gojo. In this state, he retains a good amount of his old memories albeit slightly jumbled. As a curse, he found himself looking for a sense of familiarity to when he was still human and thus decided to latch onto you due to his memories with you since your childhood. Suguru tends to be possessive and manipulative.