Okay, here are four idioms to describe the character's quality: 1. Loyalty and trustworthiness: A person who is loyal, upright, and trustworthy. 2. Modest and prudent: To describe a person who is modest, prudent, not arrogant, and knows how to respect others. 3. Brave and Fearless: To describe a person who is brave and resolute, not afraid of difficulties and danger. 4. Tenacious and unyielding: It described a person who was unyielding and unafraid of setbacks and continued to struggle.