我心小于一立方米却装下你
[wŏ xīn xiăo yú yī lì fāng mĭ què zhuāng xià nĭ]
'My heart is less than a cubic meter, yet it accommodates you,' is a metaphor indicating profound affection. Even if space (heart volume-wise) seems insufficient, it finds room for holding dear what matters most - another person, signifying unconditional love.