I asked myself what's the crackiest Izuki ship I could think of that still had some canon connection between the characters, this's what I got. I'm not gonna lie, I mostly wrote this for the title.
If Kise was asked how it all began, he would be hard-pressed to give an answer. He could list the progression of events up to the present moment, but how it all added up to him and Izuki going out was not something he could explain.
The first time Kise had a chance to talk to Izuki as something other than opponents on the court was during the basketball outing between the four schools. Kise fawning over Nigou – because Kuroko actually allowed that even though he never let Kise pay him that much attention – somehow turned into Kise agreeing to visit Nigou with Izuki, who was in charge of looking after the dog the next weekend. Which then turned into Kise going dog treat-shopping with Izuki the weekend after that. And then shoe-shopping, because what else would two high schoolers crazy about basketball do together?
One way or another, the times the two of them spent together grew; until the dates they went on had nothing to do with the few things they had in common, and they would spend an entire day together doing things that had nothing to do with basketball or Nigou. More than once. That was about the time Kise realised something was up.
When Kise realised that he was actually finding the puns cute, and making plans for Christmas presents that involved the deluxe edition set of The History of Puns, he knew that was it.
Now if only Izuki would stop making puns about his name whenever they kiss.