the manhwa definitely isn't as detailed, but if i remember correctly, haon actually goes into heat in the bathroom where he gets beat up by the alpha- eating popcorn off the bathroom floor and licking up the spilled soda when inho finds him.
haon is in heat for 4-5 days, and actually doesn't recognize inho when he takes him home and refuses to go into their home (as seen in the manhwa). inho then helps haon out for nearly a week just trying to exhaust haon so he can essentially be passed out and not have to feel hungry or feel the severe heat symptoms :(
from my memory, they never really specify if inho imprinted or bonded with haon. i think inho just wanted to help haon with his heat when he came onto him, and thought he was different from the others he slept with (he was lowkey a manwhore before haon, but there's a reason!)
sorry if this isn't making much sense, i binged it all on no sleep and might've half read some chapters lol

binged the whole novel in like 4 days, i really enjoyed it! hoping the manhwa does it justice