你有多重要只有我心里知道
[nĭ yŏu duō zhòng yào zhĭ yŏu wŏ xīn lĭ zhī dào]
This username, 你有多重要只有我心里知道, translates to 'Only My Heart Knows How Important You Are'. This implies that there's someone special to this person, whose importance cannot be measured by others but only appreciated by the user themselves, expressing a deep, personal, and possibly unspoken affection towards another individual.