
Do you remember how Yubin said his air conditioner wasn't working making his room hot? Ginu said he could stay at his place if he needed, which Yubin did. As you should know, that is when they started "practicing to do it". Although there were many chances he had to fix his air conditioner, he kept putting it off as he wanted to stay with Ginu. As time passes, he practically starts living with Ginu. Yubin should be in the clear for now, but he still will have to pay his rent, besides Ginu already hinted in that Yubin is staying with him not just because his air conditioner is broken. The whole point of the title is how they were connected by the two windows of their places next to wach other.
I'm sorry if I didn't answer your question exactly, but I hope what I told you helps you the tiniest bit out! If you have any more questions feel free to ask!

Well, the two guys have been in love with eachother since they were very young, but because of rampant homophobia & sad failed attempts at dating women causing misunderstandings, they'e never confessed to eachother.
Yubin became aware he was gay first & bought a toy. Ginu was not sure about his sexual identity until he realized that seeing a guy masturbate turned him on & that he couldn't get-it-up for a woman.
Yubin is a tsundere, so he is very easily embarrassed & cares more about how he could potentially be perceived by others that what makes him comfortable & happy. Tsunderes will never admit when they actually enjoy something because they're so stubborn & set in their ways. The way that they angry react is a huge turn-on for semes that makes them want to tease them even more.
I need as many people as possible to e xplain what happened and the effect it will have because i am soooo confused thanks.