As Man Ok and Kang Hwi talk of Jin Sae-lyung's arrival, Kang Hwi absentmindedly pulls his ring on and off. In close ups he does so with his hands before his throat. In a wide twofer he does so with his hands before his knees.
If Tae Ik owns his own house, how is it the company can move someone into it without his permission or, at the very least, informing him about it? (Along the same lines, how can they order up new construction work to his home without his okay or inclusion as to what's being done?)
Kang Hwi's discovery stems in large part from his urgent need for the bathroom, yet when he's discovered, that need disappears.
When Tae Ik discovers Kang Hwi's hideout, he enters a room where a kitten has been living, yet his allergies aren't triggered as they otherwise always are. (At this point, the kitten also disappears from the episode.)