Sto☆Mani ~Strobe☆Mania~

The heroine sees three mysterious shadows one night, and later joins the newspaper club to investigate the matter and she quickly becomes interested in a student group known as Silver Seek. SS is known across the school as a kind of intriguing, mysterious entity, but the student council is on guard because the group seems to be targeting pieces of art in the school (which for some reason are put on display around the halls). The heroine spends most of the game trying to figure out their identities and motives.

[Edited from My Neo Romance Forum]