Shota means boy. Oni means big brother. Its a story about a boy having a childcrush on the son of a the family that his family are friends with.
In the future when both are grown they will be in a relationship. But that's the future. This story is just showing a coming of age story as a child gets to terms with developing love on the person he sees as a big brother.
"The usage of the term in both Western and Japanese fan cultures includes works ranging from explicitly pornographic to mildly suggestive, romantic, or in rare cases, entirely nonsexual, in which case it is not usually classified as "true" shotacon"
It means boy, and yes it can be sexualised in shotacon, but shota itself doesn't just mean erotica. Hence why this is tagged as shounen ai and not shotacon
NVM I READ WHAT THE COVER SAYS THIS IS GROSS!