WARNING SPOILER EVANGELION 3.0+1.0
honestly I don't really care who or who is canon. what is matter to me is Kaworu feelings to Shinji is real. He loves him. He always do. if KawoRei did dating, I don't mind. even I prefer them as siblings or relatives or cousins. that would be much butter. and if KawoRei does a siblings/relatives/cousin, who Rei will end up? I think Rei will end up with Misato's son.
I read some theories from people that Rei being a mother and that's really interesting! if Rei really become a mother, my first thought whom become the father is Misato's son. I don't know why but I love the idea Rei and Misato's son together ❤️
and so, at the train where we can see Kaworu and Rei interact, I wonder what they are talking about. probably Kaworu asking Rei about his beloved nephew/niece and Kaworu wants to meet them. Kaworu being uncle to Rei's children is the cutest!
if everyone has a someone, then what about Kaworu?
the feeling Kaworu has for Shinji still exist, but Kaworu doesn't sure to whose this feelings. Kaworu always long for someone but he couldn't remember who. but when he finally meet Shinji and saw Shinji already happy, Kaworu knows whose his feelings for. because Shinji's happiness is Kaworu's happiness. they become best friend forever. maybe someday Kaworu finally date someone but I don't have a candidate who would Kaworu end up, maybe Sakura? I'm not sure. but if Kaworu didn't date, then Kaworu just living his life with cats. Kaworu has two cats he named Tabris and Karl (I imagine manga!kaworu vers lol). they are males and brothers. Tabris has white fur and Karl has orange fur. Karl is more hyperactive and always demand attention, oftenly act like a boss and the house is his. not Kaworu's. Tabris is more quiet and elegant but sometimes can act arrogant. it always pisses Karl and they would end up fight. secretly, Tabris always licks Karl's head when Karl already sleep in the middle of the night to show his brotherly-love to Karl. for Karl, when Tabris asleep, Karl lies closer and face to face with Tabris to show his loves for his brother. they may often fight during day but secretly they care each other. and that's why Kaworu already happy. Karl and Tabris also bring him happiness. Rei's children also bring him happiness and Kaworu thinks that's enough.
oh right I forgot to add that Kaworu and Kaji are best friends and they do farm together. Kaworu enjoys farming in peaceful village where Kaji, Misato, Rei and Ryoji (Misato's son) live.