Saiyan ko bhaiya bana diya? (Cashero X Bon Appétit Your Majesty)

So basically I am watching Cashero and the two character's relationship which is making me laugh is Jo Nathan and Jo Anna😭. I watched 'Bon Appétit, Your Majesty' just some time ago. And there Lee Chae-Min (Jo Nathan also played as Lee Heon) and Kang Han-Na (Jo Anna also played as Kang Mok-ju). They played the characters of being married to each other(King and Concubine or queen) in 'Bon Appétit, Your Majesty' and now seeing them Cashero as siblings is really funny to me.
I watched Boyfriend on demand in Hindi dubbing on Netflix and this made me remember the scene where the comic character Choi Si-woo had a typo mistake and one of the comment said "Isne toh Saiyan ko bhaiya bana diya" (They turned their lover into their brother)
Is it just me? (no hate to them btw)