Final Fantasy 7 vs Bleach
Connection:
Both are famous, overpowered villains to who're rivals to their series' spiky haired main protagonists (Cloud Strife for Sephiroth and Ichigo Kurosaki for Aizen)
Both were once in league with an organization (SOLDIER and Gotei 13 respectively) but ultimately ended up betraying them
Both wields powerful swords (Masamune for Sephiroth and Kyoka Suigetsu for Aizen) and in possession of an orb that makes them even stronger (Black Materia and Hogyoku respectively)
Both their final forms causes them to change appearance and have wings (Safer Sephiroth and Final Form Aizen)