This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Rubin And Ed
Ed's flashback where we discover why he and his wife got divorced she was cheating on him. Now, to make that even better, combine that with the following: his ex treats him like crap in the present and he's still somewhat in love with her regardless and has undertaken a desperate plan to try and win her back. Ed's woobie status is pretty much cemented.
Three instances with Rubin and his cat:
When asked about it, Rubin chokes up slightly and just says that he was a good cat. The guy's obviously still in mourning.