I don’t understand the ending

i interpreted it as basically karma. i believe he sees sa-chan in the girl. not only that, seems like she is the daughter of the women he cheated with and she seems like a yandere. so i think he wont truly be happy ever again.

oh no... I kinda feel bad for him despite the cheating idky...

if he talked it out with sa-chan then he wouldve been happy but nope, he decided to cheat. i do feel bad for him but i also think its what he deserves for taking her for granted