Kyoko's death in the main timeline of Puella Magi Madoka Magica. I know there are plenty madami touching scenes in Madoka (example: the entirety of episode 10), however even so this is honestly my paborito for a few reasons. Kyoko sacrificed herself to defeat Sayaka's witch, and died with her so Sayaka wouldn't have to be alone anymore. The fact that their character song,
link, was used as the ending of this episode also contributed to this, because the lyrics of the song also involve the "not being alone" concept, and it all really comes down to that Sayaka and Kyoko were both very lonely people who started out at odds, but fate ended them up this way...
Episodes nine through twelve were really very sad and would bring tears to any eye. Just the anime itself can make anyone cry themselves a watery grave of feels and tears.
I know many other touching moments from many other anime (I've watched AnoHana and Fruits Basket as well in the way of tearjerkers, which are both choc full of tears and sadness and feels), sad or not, but this one is currently my favorite.