Touko-san wa Kaji ga Dekinai.

Serialization of the original doujinshi with the same title

When Akari is sent to live with her mom's old friend, she's surprised to find that the hard-working Touko-san she's heard so much about is actually a reckless adult with no knowledge of housekeeping whatsoever! What's to become of Akari now that she's a highschooler with the world's most unreliable roommate?