SPOILER ALERT
I think it's Miss Seo. When Manseok is on the phone with his girlfriend, there's a frame of his shoe and it's the shoe Miss Seo gave him, which he also wears in the last panel. I know we don't see the shoe that the other girl gave him but she said it was simpler so I assume it doesn't have the monk strap buckles on it and also just the fact that we don't even see the shoe could be a sign that he doesn't end up with her.
I'm confuse. Wasn't the shoe he was given from Chase, the boss? I'm pretty sure he was the on giving him the shoe in the last panel
*one
it seems that op was talking about the shoes that minseok was wearing during the phone call with his girlfriend (ch61) in which we see that he's wearing the shoes that ms. seo gave him. :)
This last update got me thinking of Kirin as Hamlet for some reason idk (￣∇￣")
Same (≧∀≦)