I'm going to be completely honest in saying that Acacia will barely have any lines as you know, she doesn't have a head. In one route of the game it is possible for her to 'bloom' a head ( as she is a plant monster ) so yeah. Acacia is somewhat of a motherly figure, she is definitely the most level-headed, and mature she spends a lot of time reading ( in brail ) and looking after plants. She is not good when surrounded by lots of people as then she gets fairly clumsy and cannot understand what people are saying.