ah that's easy. list of cursed ships:
Fontcest (and au versions)
Frans (au versions count to)
Dreammare (THEY ARE SIBLINGS DAMNIT)
Chans (just no)
Chasriel (YET AGAIN THEY ARE SIBLINGS)
Soriel: (n o)
Most of the FNAF ships
Some of the Pokémon ships
I can't stress this enough: TOBY X ANNOYING DOG
I CAN'T STRESS THIS ONE ENOUGH: PAPERFRESH
Cups x Mugs. LIKE THEY ARE TWIN BROTHERS (Even tho cup is technically older but Mugs is older by a minute so.. there, twins)
and that's all I know