孟婆汤真酸
[mèng pó tāng zhēn suān]
In Chinese folklore, Meng Po is a deity providing tea to deceased souls, causing them to forget all previous lives. 'Meng Po’s tea is really sour.' It humorously refers to the bitterness or regret one has but also expresses an acceptance that all will soon be forgotten as if drinking from Meng Po’s bowl.