Ejihon Tantei Jimusho (エジホン探偵事務所), roughly "Character Picture Book Detective Agency") is an educational puzzle game developed and published by Sega. It was only released in the arcades, and only in Japan.

A duo of apprentice detectives, Temona-kun and Meruko-chan, try to catch a criminal called Phantom Dopon.

The game is a hidden object puzzle game. You get a picture which is roughly two screens high, and the picture is full of Japanese characters (kanji most of the time, sometimes kana). All characters are the same, except one. You need to find the single different character within a time limit. Your time is limited by your health, which is represented by a gauge made of hearts. The gauge will decrease over time, and you loose a full heart for every failed trial to find the character. If you run out of health, it's game over, unless you isnert credit. However, you can only use one continue for each picture. If you fail again, you get a different picture. If you find the character, you get one heart back and a number of points based on the time you took. At the top of each picture, there is a Japanese sentence which gives a hint how the differing character looks like, and if you take too long, the game will give you a hint in which direction to look.
There are mini games between some of the levels where you compete against the other character (controlled by the CPU or player 2) for bonus health.
The game can be played in 2-player-mode, with both players competing for points and health.