It looks like no one has mentioned Warrior Baek Dong Soo. Mr. Sunshine and The King in Love have strong bromances, though they are also love rivals (I guess that's technically true with WBDS as well, but I don't think anyone cared about the romance in that show). These are all Korean, though ...
For jdramas, I'd say Nobuta wo Produce. I know there are a lot more, but I haven't watched them.
I haven't watched as many Chinese shows, so the only cdrama I can think of is Love O2O, which has a group of male friends plus a bromance/romance (similar to The Untamed it's not explicit, so could be interpreted either way) between two secondary male characters. But's it's mostly a male-female romance.