我不是小太阳我只能透心凉
[wŏ bù shì xiăo tài yáng wŏ zhĭ néng tòu xīn liáng]
Here, the user is saying 'I'm not a little sun; I can only pierce to the bone cold'. This phrase reflects a state of helplessness or sadness when comparing themselves unfavorably, feeling unable to warm others and instead bringing a sense of disappointment or sorrow.