Final answer:
The passage provided does not mention a character named Summer or her preferred Halloween costume; it only discusses costume ideas between characters Helmer and Rank.
Step-by-step explanation:
The passage provided does not explicitly state what Summer wants to dress up as for Halloween. Instead, we find a conversation between characters Helmer and Rank, discussing potential costumes and the idea of dressing up as what they are in everyday life. Rank suggests that Helmer's wife could dress as a good fairy by wearing her everyday attire, which implies that the everyday self can be a costume in itself, potentially a metaphor for the roles individuals play in daily life. However, the character Summer is not mentioned in this passage, so it is not possible to answer the question regarding her preferred Halloween costume based on the given text.