Kirameki School Life SP is a bonus game that came bundled with the limited edition of Boku wa Tomodachi ga Sukunai Portable. In-universe, Kirameki School Life is a thinly-veiled parody of Tokimeki Memorial that the characters of the Boku wa Tomodachi anime play in episode 2. The anime itself is just okay, but that episode is a fun watch for anyone who enjoys videogames/visual novels. It’s all downhill from here so you can quit after episode 2.
When the characters played Kirameki School Life SP, it was funny to see them doing the exact opposite of everything you’re supposed to do in a real dating sim (i.e. being nasty to all the girls, focusing on one stat to the exclusion of all others, ignoring events), with predictably bad results. The problem is that the Kirameki game itself, in-universe and in real life, is a fairly serious and totally bland Tokimemo copy. Without the snarky commentary and bad decisions, it’s really not worth the time to play. Do please go on, this is most interesting