Lee Yong tried to push Kim Seo Bin away, but that man had such a way of blocking his path without touching him and making it difficult to reach his little brother. "Lee Whan…" He called out for his little brother angrily.
Kim Seo Bin has a younger brother and has much experience roughhousing with him growing up. He had to fight his little brother without hurting him by leaving a shred of obvious evidence on the body to avoid punishment from his parents. Over time, he learned the art of blocking his little brother without touching him when he had to stop his little brother from snooping into his work.
Kang Eun grew up with an elder brother, Kang Chin Mae. Contrary to them, Chin Mae had to spend most of his childhood days in a wheelchair. Later, his elder brother's twin joined them around to an extent, and he experienced tussling around and wrestling his elder brother - Moon Chin Hae, for unnecessary reasons.