Loyalty, a loyal friend will stick with you through thick and thin, in good times and in bad times.
He is there in times of trouble and distress unlike fair weather friends.
If he is loyal he will not back bite you, he will defend you because he is loyal to you. A true friend you can count on, a friend you can trust
The synonym of loyalty can be loving kindness, meaning he loves you and treat you with kindness. Isn't that a good quality of a friend?