Responses
No it wouldn’t, because mungmung fell for saheon even though saheon only treated him as his non-biological sibling! In the novel, during this time (chap 10+) is when saheon developed feelings for mungmung because only then did he realize how pretty he was and saw him as a potential partner (he is straight until meeting mungmung again at the airport)

is this considered ,, grooming (⊙…⊙ )
i mean, im still gonna read it ,,,,,, jus curious if their story falls under that category lol