三寸心脏你是信仰
[sān cùn xīn zàng nĭ shì xìn yăng]
This internet name metaphorically means that 'You are the belief within my tiny heart', implying an intense love or belief for someone. Chinese people often refer to the size of their palm and depth of their affection by using the unit 'inch'. In the context of this idiom, 'three inches' is meant to symbolize the small but concentrated nature of a heartfelt feeling.