Read Hidaka Shouko's works. Especially Hana wa saku ka and Yuutsu no asa.
i actually thought the same thing when i first started reading this manga- i thought it was just a bunch of sex and fujoshi 'fan service' which was really disappointing for me, but i stuck with it and i'm honestly really glad i did. the beginning is really just a bunch of 'foreshadowing' but with the past as opposed to the future. i saw you said earlier in a reply (from one of the few that actually answered you civilly) that you wouldn't mind the smut so much if it seemed there was actual reason for it, and i personally think that the 'reasoning' behind the smut actually makes sense later on in the story- not to give too much away, but shirotani's disorder is largely due to a trauma involving his sexuality. idk if kurose knew that at the beginning of the manga or not, but he also has his own reasons for wanting to be extremely close to shirotani that stems back to another trauma in HIS childhood (these poor boys had messed up childhoods (￣∇￣") )
obviously its up to you if you decide if you want to stick with it, but i would personally recommend you do if you want a story where the characters have to heal mentally in order to have a lasting relationship :D (also, if it helps, the smut kinda plateaus at a point in the manga, so the excessive smut stopped being an issue for me (or maybe i just thought it plateaued because of the wait in between chapters idk *_*))
so im on already on chapter 18, and there really doesn't seem to be much plot. Just a lot of sex, and slowly getting over his phobia. Does this manga ever get deeper, where there's more to the relationship then just smut? x: