In order to trigger this tiny quest you need to fulfill two requirements:
- Complete Acting On Your Best Behaviour, a main story quest involving Eugene. You'll need to explore the majority of New Wirral to finish the questline.
- Raise your relationship with Eugene to at least the second level. You can't do this until you've completed Acting On Your Best Behaviour.
Once you've accomplished those two things, pay a visit to the Francophone Café in Harbourtown. One of the Landkeepers will shuffle in, and she is obviously struggling with the loss of her purpose now that the organization is bankrupt. Kayleigh will name her Sunny, and decide to get her some new clothes.
Use the lift on the east side of Harbourtown to get to the upper level, then check to the west. There are two shops, and the clothing store is the shop on the right. Head inside to watch a cut scene where Sunny gets a makeover. The quest ends soon after, and you'll receive Fused Material, an Upgrade, and a bunch of materials for helping Sunny. She will hang around outside the clothing shop from that point on.