Moderate spoiler warning for one DEARDROPS ending.
On 26 September, MangaGamer released the Kira☆Kira + Deardrops crossover visual novel d2b vs DEARDROPS -Cross the Future-. It was originally released 2011 in celebration of creator OVERDRIVE’s fifth anniversary. This is an all-ages VN, and there is no Japanese version with erotic content. Both members of the crossover are VNs with a strong musical theme, where the main characters form a band and rock out in your general direction.
There are already some points of contact with the story of Kira☆Kira in DEARDROPS, where you actually meet the now-successful singer Kirari, the “main girl” from the previous VN. It only makes sense to make a delicious crossover, does it not? For the Kira☆Kira part, the fandisc seems follow the usual combined-routes-no-girl-picked. The ending picked for DEARDROPS seems close to Riho’s ending.
The plot is basically this: Shoichi has been away from DEARDROPS for three years playing the violin in Germany. Called the “violin prince” prior to getting kicked out of his orchestra at the start of DEARDROPS, he’s now an even better violinist. Riho randomly sees him and Kirari performing together abroad on TV, and when she sees how much Shoichi is enjoying it, she feels this urge… and wonders if she could do better than Kirari. Due to plot, she actually gets the opportunity to face her – but who will win?
Well presumably none of them, this kind of story doesn’t usually work out that way.
Besides d2b vs DEARDROPS, you can also buy Kira☆Kira and DEARDROPS at MangaGamer (NSFW). Be aware that though this VN has no erotic content, both its predecessors do; of the two, only Kira☆Kira has an all-ages version. MG has also translated the FD to Kira☆Kira, Kira☆Kira Curtain Call, which you can buy bundled with the main VN for a decent discount. I personally did this after originally pirating Kira☆Kira, but I never got around to reading the FD – bluh, one day…