Why are there not more Tonks/Remus/Sirius OT3 shippers? It is perfect.
Tonks and Sirius are related
Technically, they’re first cousins once removed (Tonks’ mother is Sirius’ cousin IIRC). There’s no reason they couldn’t have gotten together - both Harry and Remus considered it a possibility that Tonks loved Sirius romantically.
Furthermore…like…the Black family tree? More like the Black family knitting ball. Purebloods, man. Your options start to get limited after a while.