Peddler in Another World: I Can Go Back to My World Whenever I Want! Volume 5 by Hiiro Shimotsuki

After rescuing Aina from the clutches of her kidnappers and successfully reuniting Suama with her dragon mom, Shiro is more than ready for things to calm down a bit and for his life in the other world to finally return to some semblance of normality. Unfortunately for him, it isn’t long before trouble crosses the threshold of his store again in the form of a total bombshell who claims to be the dragon Shiro had last spoken to only days before. She isn’t the only unexpected visitor though, as Aina’s abductor and Suama’s former pursuer, Celes, also turns up on his doorstep, having decided she would become Shiro’s slave to repay him for all he had done for her. And the worst part? Both women absolutely despise one another. In the midst of the ensuing chaos, Shiro receives a strange letter from a good friend of his, urging him to drop everything and come to the royal capital. Worried that his friend might be in trouble, Shiro sets off for the distant city. But what awaits him there?