Ikui Shrine is a small shrine in Katsuura Town between temples 19 and 20 of the Shikoku Pilgrimage.
Ikui is another way of reading Ebisu, and this is the kami enshrined here, rather Kotoshironushi, the official identity of Ebisu since the Meiji Period.
The shrine is listed in the Engi Shiki, a court document from the early tenth Century that, among other things, lists 2,861 shrines across Japan that received annual offerings from the Imperial Court.
This website has details of all the shrines in the Engi Shiki, unfortunately only in Japanese.