YAOI FAN！

Anime couples：

US X UK, RUS X CHN from Hetalia.

L.Lawliet X Light Yagami from Death Note.

Hattori Heiji X Kudou Shinichi, Hakuba Saguru X Kuroba Kaito, Akai Shūichi X GIN(well, pardon me) from Detective Conan.

TV couples:

Sherlock X John from BBC Sherlock.

Arthur X Merlin from Merlin.

These are not the all. :P