which comics is stucky (fandom) associated with?
Marvel Comics.
Stucky (fandom)
In fandom, Stucky (also Steve/Bucky or Bucky/Steve) is the pairing of Steve Rogers (Captain America) and James Buchanan "Bucky" Barnes (the Winter Soldier), fictional characters who appear in comic books and related media produced by Marvel Comics. 
wiki:9503462
Stucky (fandom) [SEP] Introduction
In fandom, Stucky (also Steve/Bucky or Bucky/Steve) is the pairing of Steve Rogers (Captain America) and James Buchanan "Bucky" Barnes (the Winter Soldier), fictional characters who appear in comic books and related media produced by Marvel Comics. The pairing is a manifestation of shipping, a phenomenon in fandom wherein individuals create fan works that depict a romantic or sexual relationship between two characters whose relationship in the source material is typically neither romantic nor sexual; Stucky is an example of slash, a genre of fan works that focus on same-sex characters. In accordance with shipping naming conventions, Stucky is a portmanteau of "Steve" and "Bucky".