
I think its bec they know how difficult their son is (cant stand stupid people, domineering) lmao. Plus the aspermia diagnosis on SeungHyeon. Thats why for them, Hosik is a miracle. Maybe in their minds, if SeungHyeon didn’t met Hosik, their son would remain single and childless forever.
And this is just me, but I think even his parents are not keen to challenge SeungHyeon. Their son is a brilliant business and family man. He is actually an ideal chaebol son. Thats why protesting SeungHyeon’s choices would seem ridiculous and unproductive.

Ofc they love and adore Hosik. They respect and treasure their son. But the premise of the original comment is why SeungHyeon’s parents seems chill and accepting of his choices, giving minimal resistance to SeungHyeon’s decisions, thats why I said bec they know how domineering their son is. Bec lets accept it, SeungHyeon IS domineering. He sometimes even have a one track mind. The way he pursued Hosik is a good example of that. Thats why many readers tagged him as a red flag.
Not just his parents, I think SeungHyeon’s whole clan has an idea how obstinate and goal oriented SeungHyeon is…and how brilliant he is at producing results. In a way, those traits of his factor why his family doesn’t challenge SeungHyeon openly. They adore Hosik, who wouldn’t, but aside from that they trust SeungHyeon’s cunning and ability to get what he wants and trample those who would think to oppose him. Thats why there is a panel of Hosik telling his mother that SeungHyeon’s company has no inheritance struggle. Thats a clue that no cousin of his is challenging SeungHyeon for the heir position.

they were not afraid of him in the sense that “he will kill his parents if they oppose him” way. thats not what i meant. think they are scared, given that seunghyeon has aspermia, that if they oppose the match between hosik and seunghyeon, that seunghyeon will choose to be single and childless as a way to rebel for not getting what he wants. i think his parents know how difficult seunghyeon will be as an opponent. that their son is capable of making them regret opposing seunghyeon’s desire to marry hosik. thats why rather than test that out, they chose to support seunghyeon’s decision bec truly, what is there to lose? they are gaining a son in law whom their son adores plus a grandkid.
seunghyeon’s parents are clearly smart that they chose the path with least resistance when it comes to dealing their equally smart and yes, domineering like his mom, son.
Nobody's talking about this but props to Sunghyeon parents for being so chill and welcoming Hosik with open arms and be the best cool grandparents ever.