Excel Walter is the grandmother of Carla Vargas and Juna Doma as well as mother-in-law to Castor Vargas who was formally the admiral of the Navy and she is currently the supreme commander of the National Defense Force.

Excel possesses a keen mind and shares several realistic viewpoints with Kazuya Souma. She will do what is necessary to safeguard her people and her long years of experience aids her in making key decisions. She will show no mercy to her enemies and is a shrewd tactician.

Despite having numerous husbands through her long life she is known for being committed to each of her past husbands and staying with them till the end.

(Source: How a Realist Hero Rebuilt the Kingdom Wiki)