The Afterwords title is clearly a reference to Oregairu.
Oregairu original title:
やはり俺の青春ラブコメは間違っている
(Yahari Ore no Seishun Love Come wa Machigatteiru)
“My youth romantic comedy is wrong, as I expected”.
Afterwords title:
やはり俺の水着選びは間違っている
(Yahari Ore no Mizugi Erabi wa Machigatteiru)
“My...