相濡以沫1m厮守终生1m
[xiāng rú yĭ mò 1m sī shŏu zhōng shēng 1m]
Refers to enduring companionship throughout life, derived from an ancient story where fish kept each other alive through moistness when trapped together. 'To nurture each other with saliva and stay together forever' symbolizes mutual care and devotion in a long-lasting relationship.