Kimimaro Kaguya has two dots on his forehead. In South Asia, it is called a bindi. Is it an identification mark, or does it have any significance like a curse mark? Is there any canon reason given for it?
I came across a source which said that it represents his clan, but the Kaguya clan doesn't have significant history in Naruto/Shippuden anime or manga. Is there any source for this claim?
All Kaguya clan members have that two-dot mark as their trait, just like how the Uzumakis have red hair, Uchihas with Sharingans, Yamanakas have blonde hair and greenish eyes, Hyugas have Byakugans, etc.. It's done to make the clan member stand out from other clans and clan members and to identify exclusively from which clan the Shinobi is from. Mangakas do this so that the readers don't get confused and also to have a good amount of distinction between each clan and their members.