Okay, that's a new take on the "interrupted by fireworks" trope.
I'm fine with that, I like when authors bend their tropes. Also, Senpai probably shouldn't be involved in a steamy make-out session while recovering from a concussion.
"Oh no, not the same trope again!"
The thiing is, it's not quite the same. What is happening is a mirror to what happened earlier.
First, Minami reveals that she's going abroad. Tsubasa thinks "Oh no, I'm going to lose my precious friend for a long time!" which seems to make him consider...
So, pimp out the little sister? I am... conflicted.
Edit: not the little sister, I got things mixed up. Thanks to @Eksentrysyti above for the explanation.
I see your true colours shining through
I see your true colours
And that's why I love you
So don't be afraid to let them show
Your true colours, your true colours
Are beautiful like a rainbow