SEGA is a Japanese entertainment company known primarily for video games. They were originally founded in 1960 as an arcade and slot machine manufacturer and eventually expanded to the home console market where they released such systems as the SEGA Dreamcast, SEGA Saturn, and the SEGA Game Gear. While they no longer produce their own consoles, they still continue to develop video games to this day. Some notable SEGA gaming IP include Sonic the Hedgehog, Puyo Puyo, Yakuza, and Super Monkey Ball.
Alongside their gaming endeavors, SEGA also actively produces toys under their SEGA Fave (formerly SEGA Toys) division. The branch originated as an electronic toy company named Yonezawa and was sold to SEGA in 1994. SEGA Fave has collaborated with various IP throughout its history with some of its toy licenses including Magic Knight Rayearth, Disney, Anpanman, as well as being the Japanese distributor for Fur Real Friends. They have also worked with companies like Sanrio and San-X to co-produce the Rilu Rilu Fairilu and Momobuta lines respectively. SEGA Fave is probably most notable for creating toy IPs that incorporates gaming into their play styles, such as their educational plug-and-play consoles, the SEGA Pico and Beena, and their Mushi King and Love and Berry franchises which combined trading card collecting with arcade gaming.
SEGA also produces collectible figures based on various anime, manga, and pop culture franchises. They are often designed specifically as crane machine prizes. While these figures are generally handled separately from their main toy branch, they sometimes pull from the same IP pool and occasionally include dolls.

List of Doll Lines Made by SEGA
NOTE: This section does not list dolls based on SEGA video game IP produced by other companies.