More Puzzling Than A Riddle is a Manga/Manhwa/Manhua in english language, SUGGESTIVE series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

What you need is "inspiration"! This is the beginning of a youthful riddle-solving comedy! Jyunino Saki, a student at Meichi Academy, is a highschool girl with impeccable looks and academic ability, but has an unusual fondness for solving riddles. Ichinose Eita, a new member of the club, is taken in by Saki, and is forced to solve her riddles every day after school! Dreaming of a sweet school life with a beautiful senior, he spends the day solving riddles again today. No advanced knowledge or difficult calculation required!