Shinpei Ajiro is the main protagonist of the Summer Time Rendering series. He returned to his hometown of Hitogashima for the first time in two years to attend the funeral of his childhood friend, Ushio Kofune. Since he lost his parents at an early age and grew up in the Kofune family, he has been close to Ushio and Mio as if they were his family.

Spoiler

Ever wonder why Shinpei is drawn with different colored pupils or irises? it is the eye of Haine, the original shadow. It originally belonged to Haine but after leaving it, this eye was granted as a gift from Ushio to Shinpei. Following the information cited by Shide, this right eye has the power to control time, unlike Haine's left eye which can see time. With this eye, Shinpei receives various types of sub-skills, the most common, and most used is that of observation; By observing various parallel worlds with this eye, he can choose which world he will enter, and according to Shide, there is a likelihood that there are several types of world, such as a world where Shinpei and everyone in the village die for Haine and Shide, or a world where Shinpei conquers the shadows and peace blooms again on Hitogashima Island, or a world where the people he loves so much are slowly dying, and so on. This eye in question also gives a certain level of premonition, not least because it can see parts of the future thanks to its time travel. With this eye he can also travel in time, and even take someone with him, or he can use that eye to regenerate himself from injuries or problems that he started to face in each time loop he lived.