is a character popularized in Hokkaidō

Hokkaido

, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. Much like the Tamagochi, the name "Marimokkori" is a pun: marimo

Marimo

, also known as Cladophora ball, Lake ball, or Moss Balls in English, is a species of filamentous green algae found in a number of lakes in the northern hemisphere. A marimo is a rare growth form of the species where the algae grow into large green balls with a velvety appearance...

 is the word for the green algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

 clusters that grow in some of Hokkaidō

Hokkaido

, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...

's lakes, while mokkori

Mokkori

is a Japanese sound symbol word that essentially represents the "sound" of something sticking out in a flat surface, or the sound of something rising very quickly. A popular term with fans of 1980s Japanese animation, it was popularized in the manga and anime City Hunter by Tsukasa Hojo...

is a Japanese

Japanese language

is a language spoken by over 130 million people in Japan and in Japanese emigrant communities. It is a member of the Japonic language family, which has a number of proposed relationships with other languages, none of which has gained wide acceptance among historical linguists .Japanese is an...

 slang term for an erection

Erection

Penile erection is a physiological phenomenon where the penis becomes enlarged and firm. Penile erection is the result of a complex interaction of psychological, neural, vascular and endocrine factors, and is usually, though not exclusively, associated with sexual arousal...

.

Marimokkori's fame comes through merchandising

Merchandising

Merchandising is the methods, practices, and operations used to promote and sustain certain categories of commercial activity. In the broadest sense, merchandising is any practice which contributes to the sale of products to a retail consumer...

, with a number of various souvenir

Souvenir

A souvenir , memento, keepsake or token of remembrance is an object a person acquires for the memories the owner associates with it. The term souvenir brings to mind the mass-produced kitsch that is the main commodity of souvenir and gift shops in many tourist traps around the world...

s being sold in Hokkaidō and throughout Japan.