You can't feed pink keys to kurito because you get them for 'free.' You get a pink key with every N-Gacha ticket.

Sure, I didn't get to open as many pink boxes I'd care for, but the pink boxes were crap anyway. Do I REALLY need another 1000 pero? An N-Wild?

Pfft.

I'd rather that people opened my gold and silver boxes so that I can MAYBE get something decent. And radars were NOT rare. I have over 100 of them. So many, I fed some to Kurito just to try to get a good card or some glasses. It didn't work, but I got a 3SR Wild for my efforts.