OTT Sweet Lolita is a substyle of Sweet Lolita that focuses on looking as cute/kawaii and decorated as possible, the style itself takes elements from Decora, Fairy Kei, and Himegyaru fashions, such as bouffant hair and exessive accessories. OTT stands for "over the top" and the style is exactly that!
Dresses in OTT Sweet Lolita are typically pastel, often featuring several different pastel colors together. Sometimes they will be sightly shorter than standard Lolita dresses, but not always.
Wigs are a common accessory with OTT Sweet. Generally, long curly wigs, many times in unnatural colours, are the favoured choice. Split, or two tone wigs are also common..
OTT Sweet coordinates often feature more accessories than usual, especially hair accessories.
The term "OTT" can be applied to any sub-style that is over-the-top as well.