The muscle turns the color of deep charcoal and hardens so nothing can pass through the walls. It absorbs warmth without reflecting any light back out.
Example Usage
Thai: เขาใจดำมาก ไม่ยอมช่วยเพื่อนเลย
Transliteration: khǎo jai dam mâak, mâi yaawm chûay phûean looei
Translation: He is very mean and refuses to help his friends at all.