The stairwell scene initially got me squealing because of the progression of their body language (I'm a sucker for physical 'choreography')...but of course it's also a visual representation of how their relationship is progressing.
Many have mentioned how wonderful this scene is and it IS fabulous because it's so simple. It's nothing big and flashy. It's quiet and mundane, a simple conversation in an empty stairwell. But what is shows is how Tinn and Gun are feeling more comfortable to reveal little snippets about themselves, about their childhood, and the things they love to do. And more importantly to reveal the things they're embarrassed about, and to realise the other person isn't as 'perfect' as they thought (because who is?).
And all this humanises them beautifully in each others eyes and ultimately allows them to settle into that comfortability even more. They can read each other's energies and switch the mood. And they feel brave enough to offer compliments and say things that will make the other feel good. It encompasses everything in the journey from idolisation to the reality of the other person - the genuine 'getting to know your crush' experience which we often don't get in shows.
I'm so happy the writers/director had this scene in the show because, even though the 'date' (booth inspection) also showed us they were getting closer, that was still them with things to distract them from what it really meant for them to be spending time together, whereas this conversation - alone and with no background music - allowed them to zero in on each other and open up about themselves, being brave to show their vulnerability, and to let the other in. And it was so important for us to see that too…to know that this is the genuine experience - not just the fluffy 'date', eating cupcakes and winning cuddly toys - but stopping and seeing and learning and listening.
It's nearly four minutes of simple perfection that takes their relationship leaps and bounds further than the flirty interactions and, yes, even Tiw's help. And it's this that has ultimately enabled them to go from the flustered uncertainty after Tinn lifts Gun up by the tree to the fabulous pinky hold at the end where they're both aware of how the other feels. It's just so wonderful and this whole show is a gift.