Casca is the deuteragonist from the anime and manga series, Berserk. She was a member of the Band of the Falcon with Griffith being her leader, later the band recruit a mercenary named Guts who she resentful towards later falling in love with him. (Extract from Heroes wiki)

In this scene, Casca goes to visit guts to treat his wounds from after his battle fighting 100 soldiers. This is a quiet scene, as Casca and Guts talk about the band of the hawk, their hopes and dreams. This is also one of the first scenes where Casca and Guts are seen closer as friends than enemies.

For Casca's voice, anything goes. You can try sound similar to the official castings of Casca or go for your own interpretation. Just stay true to the character and most importantly, have fun.