你是我心底最完美的缺陷
[nĭ shì wŏ xīn dĭ zuì wán mĕi de quē xiàn]
Translated into English: 'You are the most perfect flaw in my heart.' It indicates that despite some shortcomings of the person (you), the user accepts these faults wholeheartedly and considers them beautiful and unique parts of 'you'. This might suggest an imperfect yet treasured relationship or person in their heart.