guilty pleasure

Translations
тайное удовольствие
Eating chocolate late at night is his guilty pleasure.
Есть шоколад поздно ночью — его тайное удовольствие.
Definitions
A guilty pleasure is something that one enjoys despite knowing that it is generally considered to be bad, embarrassing, or socially unacceptable. It often refers to activities, entertainment, or foods that provide enjoyment but may not align with one's usual tastes or values.