That's Not Just a Reward

Yu-Gi-Oh cards \o/
And I say you this: If a boy is ready to trade in his most valuable card for the panties of a girl it†˜s clearly true love!

When you trade in a card worth...50000 Yen...! For a pair of panties belonging to a girl, well...True love?
'Dirty old Baldy', though...I wonder who she's talking about?
Her brother, his friend was kind of a nice guy too. Like, he 'tricked' his friend into coming over, thus basically being a wingman for the two, and yet he was also worried and wanted to go save his friend.
GREAT ENDING THOUGH! Heh, I guess to his friend, it would seem like our protagonist just decided to swipe panties again but is instead more emboldened and is wearing it on his head. Seriously though, his face at the end was just priceless.

Disregard rare cards worth Y50K ... Itsuki Knows What Is Best In Life; namely - the scent of his best friend's 'nee-san'.

Well, in the end Itsuki and Kisara-Nee-san seem to be fine with the (*cough-cough*) arrangement ... although perhaps he'd better remove the pantsu from his head before going out in public.

Japanese deadpool?