Anata no Koigokoro wa Machigai desu!

Due to unavoidable circumstances, researcher Elze finds herself attending a matchmaking party next month. A friend in a similar situation asks Elze to create a love potion for her to use on her crush before the party. But... she accidentally uses the finished potion on the very person she's had a crush on for five years! "Miss Elze, I love you. I want you to be my girlfriend, with marriage in mind." The knight suddenly begins to woo Elze, leaving her bewildered. Precisely because she loves him, she can't accept a confession made under the influence of a drug! The knight, who was supposed to be taciturn, suddenly becomes incredibly talkative, spouting sweet words of seduction. Elze desperately tries to resist, but... "I can't accept. Your feelings are wrong!" A battle of wits between an aggressive knight and a researcher who wants to escape! (Source: Kadokawa, translated)