18+ Elf no Kuni no Kyuutei Madoushi ni Nareta node Himesama ni Seiteki na Itazura wo Shitemita

Keith Blackhound was expelled from his Order for selling voyeur photos. After that he wandered around doing random business by making weird magic items, occasionally scamming people by selling his failed products. One day, after being discovered selling fake love talisman, he was chased by Temple Knights then somehow ended up getting lost in the Elven Forest. At that moment he saw several elves being attacked by a basilisk, he went to help them expecting food as reward. He successfully repelled it with another one of his weird product and as he wished he received food as a reward from the father of one of the elven girls. The father turned out to be an influential person in the kingdom and took a liking to him. He was recommended to be Court Magician by him and was accepted. His first duty is to teach Elven Princess Naia, who despite being an elf, is unable to use magic.

(Source: Novel Updates)