西瓜卖萌娶了夏天抛弃了我
[xī guā mài méng qŭ le xià tiān pāo qì le wŏ]
Translating into 'watermelon acts cute marrying summer leaving me behind', it humorously depicts how watermelon seems playful in summer but forgets about oneself (in winter). It's a whimsical way of expressing loneliness or being neglected.