here are the last names i Headcanon for omori characters (if y'all have any suggestions feel free to tell me, i might change it)
Hidaka (for mari and sunny): the first part of this means "sun" or "day" and considering Sunny's first name its kinda a funny pun. The second part means "high" or "tall" which is also kinda a pun bc they both died falling from high places
Duran (for Hero and Kel): Duran is a spanish surname that means "Enduring" I think this fits Hero and Kel well because after Mari died, Hero went into a state of depression which he had to endure and even though Kel represents acceptance, he still had to endure the pain of Mari's death
Tristesse (for Aubrey): Tristesse is a french name that literally means "sadness" and is often associated with misfortune. This fits Aubrey perfectly because of her situation with her parents and mari's death
Cheran (Aubrey part 2): Cheran is a biblical name that means "Anger" which fits her because she represents anger and its also a biblical name and Aubrey started to go to church after Mari died soooo (i hc that Aubrey doesn't like either of her last names bc she doesn't like her parents and each name is either her mom or dads so if she has to use one she'll use both but after the truth she starts to use Duran)
Demetriou (for Basil): Demetriou is a greek name that names "Child Of Demeter" which fits him because he likes plants and Demeter is the goddess of plants