He was just sitting under a tree until Tanjiro, Zenitsu and Inosuke go up to him randomly. They had smirks on their faces Mui: "god, wtf did you idiots do now–" Tanji: "we gave Astro a " doll " of youuu~" Ino: has a stupid smile across his face Zen: "a voodoo doll~" Mui: he turns just a little red "a..voo.."