whoops got tagged twice (thanks @Prometheus, @Jenny-Toons )
Gonna keep in universe with Robin and add two more characters (if that's okay ^^;: )
starting off with Dai (they/them)
Dai is a sort of shapeshifter specifically taking the forms of animals, mainly taking the form of a wolf or a bear depending on what feels most necessary or most comfortable. They start off as a lone wolf having fended for themself most of their life but eventually become a long time travel partner and close friend of Robin's. They're not without their secrets tho and only ever share things with those they truly feel that they can trust so anyone who is considered that close is often very important to them.
the other oc i'll add is Sprig (he/him)!
Sprig is a sort of rouge who tends to do essentially whatever he pleases. He's a sucker for treasure and if something shows promise of a large reward it's very possible to find him there. He's also a skilled archer (easier to pick off the competition from a distance) so outside of treasure hunting it's possible to find him honing his skills, hunting game/monsters for profit or spending gold on maintenance of his gear and buying shiny new toys to play with. Despite his ocassionaly arrogant attitude he does have a capacity to care for others especially those who are important to him.
as for summoning i call @SourLemons90