A Dotera is a padded kimono jacket worn during the winter in Japan for warmth.
Either lined with cotton or made with thick wool, the dotera is usually regarded as a type of casual wear jacket and has become associated in modern culture with being worn by those who do not care about their appearance (much like tracksuit pants/jackets).
- Naru tended to wear a simple dotera over a jumper and tracksuit pants while studying in her room. After Keitaro arrived she altered her dress sense to be more presentable.
- When Shinobu and Motoko took up studying, they momentarily sought to impersonate the way Naru did it and also wore dotera and tracksuit pants while studying. They also each got replicas of Naru's thick-lense glasses to complete the effect.