The biggest hint is in the picture. is clearly illustrated in the same frame.
 So this refers to , or the place next to Ren. Of course it indirectly refers to the position as Ren's best friend, too, where Makio could feel comfortable and secured. is the te-form of meaning "to make/keep (room)".
This comes with dots simply because the author knew it's a tricky part that needs special attention to interpret. Even a native speaker takes a few seconds to notice that refers to this position, and this small trick makes this frame dramatic.