Is this all worded and structured correctly?

FYI- Kitiara is the highlord, Tanis is the half-elf, and Laurana is the elven woman. Tanis offered to trade himself to Kitiara if she would release Laurana, and the highlord accepted the arrangement. However, Kitiara planned to break her promise to Tanis since she had already decided that the only way to make the half-elf totally devoted to her was to destroy Laurana and give the elven woman’s soul to Soth.