Does the little guy have dwarfism or something?

Probably not, I think the artist just likes drawing chibi characters. His other works usually have one character with the same phenotype.

Oh okay, do you know if his other works are on this site?

Yeah they are:
https://www.mangago.zone/read-manga/shinobuna_chiyo_chan/
https://www.mangago.zone/read-manga/katagi_modoshi/

Thank youu!!