^ As a girl, I just thought people with scars are either really aggressive and pick a lot of fights or super clumsy and trip all over the place all the time.
Sophia may be assuming that Catarina is straight because her previous self was. If she can get her to marry Nicol, Sophia will automatically become the 2nd most important person in Catarina's life. However, her truest feeling came out when they were stuck inside the book together.