Here is a list of airlines serving Sevilla Airport:
Here is a list of airlines erving Cleveland Airport.....
There does not appear to be any direct flights from Cleveland into a European hub.
A check on the Cleveland Airport interactive route map show none of the US airlines are offering a through routing from Cleveland to Sevilla.
However, have a look at klm.com and airfrance.com. They do offer routings from Cleveland via Detroit and Amsterdam into Sevilla. Be aware that in December, prices will rise considerably after mid-month because of Christmas.
As Cleveland has no direct flights to European hubs, a minimum of three flights will be needed to get into and out of Sevilla.