best bromances (not BL)

I'd say Guardian: The Lonely and Great God (Goblin) has a decent bromance. Also, Good Manager (Chief Kim).

The Blood of Youth was also lovely bromance. 

Man To Man - spy is assigned to be bodyguard for an actor who is invited to social situations that the spy needs to infiltrate

https://mydramalist.com/16977-man-to-man

Mysterious Lotus Casebook

Under the Skin

Oh No! Here Comes Trouble

Secrets in the Hot Spring (it seems like it might be BL, but it's actually not. It's bromance. )

All of the 'High&Low' movies/shows. 

Junkyouju Takatsuki Akira no Suisatsu

Dorokei

Duel has a bromance where they start out with one hating the other. So does Flower of Evil and Kimi to Sekai ga Owaru Hi ni ,

Also the MLs of these have good bromances

• Meteor Garden/Boys Over Flowers/Hana Yori Dango/F4 Thailand: Boys Over Flowers 
• Cinderella and the Four Knights 
• Dear Diary 
• Fireworks of My Heart (all the firefighters)
• Flower Crew: Joseon Marriage Agency 
• From Now On, Showtime! 
• I Am the Years You Are the Stars 
• Love Between Fairy and Devil (two, one is enemies to kind of frenemies)
• Love in the Moonlight