Sometimes you just come across things that are utterly delightful, but you can't really remember how you got there. That's how these two series are!
The Captive Prince trilogy by C.S Pacat is what one person called a cross between Game of Thrones and Brokeback Mountain. It's a slow burn with lots of tension (both suspense and romance) with interesting characters and great world building. Expect the first book to really set the stage for all hell to break loose in books 2 and 3.
"When beloved warrior hero Damen's brother siezes the throne of Akielos unjustly, rightful heir Damen is sold as a pleasure slave to Prince Laurent of the enemy Vere Kingdom, and is soon caught up in court intrigue that threatens him and his new master."
The World's Greatest First Love by Shungiku Nakamura is a gay romantic comedy manga series. It follows the lives of several different editors within a romance manga magazine department and their love lives. While the characters and some of the story line tends to be formulaic (strong silent type, sensitive wear's heart on sleeve type, etc.), Nakamura does a great job balancing between comedy and romance. If you're looking for a fun page-turner with a bit of steamy romance this guilty pleasure is for you!
"When Ritsu Onodera changes jobs, looking for a fresh start, he's not exactly thrilled when his new boss turns out to be his old flame. Ritsu's determined to leave all that in the past--but how can he when his boss is just as determined that they have a future?"