sheepish
/ˈʃiːfɪʃ/Definitions
1. adjective
Feeling or showing shame or guilt, often in a foolish or endearing way.
“After getting caught lying, the boy looked sheepish.”
2. noun
A feeling of shame or guilt, especially one that is regarded as endearing or amusing.
“His sheepish expression told her that he had indeed eaten the last cookie.”