In fan art she is normally shown picking on Reisen.
In many fanworks, Tewi appears to be a fraudster, constantly deceiving other people and taking advantage of it, or even backstabbing someone. One of Tewi's Japanese nickname is Usagi(う詐欺). It sounds same as "Rabbit", but its Kanji, Sagi(詐欺) means "Fraud". It is because Tewi's origin, White hare of Inaba is cunning white rabbit deceiving other animals.
In fanworks, Reisen and Eirin treats her like baby. But in fact, Tewi is much older than Reisen or Eirin, and the building site of Eientei in Bamboo Forest originally belongs to Tewi.