Mama Kannon is the only shrine in Japan dedicated to the female breast. Officially it is called Ryuonji and dedicated to the deity Senju Kannon. This Kannon vowed to work unceasingly until all sentient beings could be free of the cycle of suffering, and split its body into 1000 heads to witness suffering, and 1000 arms to alleviate it. People pray at the shrine for safe delivery of babies and for healthy breastmilk production. So you'll find many breast-shaped items around the temple.