ShinyDoll is a Japan based BJD company, formed by artist Doi Shin who also works as representative.
As of August 2019, ShinyDolls appear to no longer be available from the artist or through dealers.
Shinydolls are engineered with superior posing in mind, and so far come in 1/6, 1/4 and 1/3 size. They are female only and most of the facial sculpts have a realistic aesthetic, although there have been some Anime styled sculpts released. 
The Thaasa line were the first dolls released by Shinydoll. The dolls are around 56cm tall with a very slim, mature body shape. They are double jointed at the knee and have a single joint at the elbow with the same flexibility of a double joint. The Thaasa III and later releases have a ball joint hidden in the top of the neck for improved neck expression, and a twisting joint on the upper arm. All releases have a twisting thigh joint for suwarikko sitting, and grooves on the back of the thigh for Japanese kneeling.
The Thaasa body has smaller feet that most 60cm dolls, and can wear shoes intended for Dollfie Dream and Obitsu dolls. Clothes for the smaller/regular chested versions of these dolls, as well as Luts Delf, also fit well.
The Fragille line are slim minis and are around 42cm tall. Their jointing system is identical to Thaasa III bodies, but the aesthetic is slightly different, as they have a smaller chest and larger hip than Thaasa. A new body, the Fragille II, has been released with improved posing.
Fragille is similar in size to Unoa and Minifee, and can share clothes and shoes, although Fragille's feet are slightly narrower than Unoa.
The Pricco line are child=like tinies, and newest Pricco III are 32cm tall. They are more mature and slim than Yo-SD or Littlefee dolls, but are roughly the same size and can share clothes and shoes, although both can be a little wide for Pricco.
Shinydoll resin is very close to Unoa and reasonably close to Volks resin in colour, and this coupled with Shinydoll bodies having a large posing range makes them good potential for hybriding. However, Shinydoll necks are generally quite slim and the shoulders small, meaning many heads can look 'bobble-headed' on them. Smaller Yo-SD heads work very well on the Pricco body, and Unoa heads are a good match for Fragille.