Responses
Read these two in this specific order, tho not a sequel they're kinda connected, also don't be put off by the art at the start, it changes for the better in just a few chapters :
Song of Reverberation
https://www.mangago.me/read-manga/song_of_reverberation/
The Promise
https://www.mangago.me/read-manga/the_promise/
Looking for other shounen ais like At The End of The Road, same tension and everything.