Sebastian usually doesn't have a lot of spare time, being the butler of his young master and maintaining the household during the day. Entertainment establishment such as this one falls under public promotions and relations when he needs to represent the Phantomhive brand for the Young Master's company.

So usually, Sebastian comes much later in the evenings after serving dinner, with him managing the staff he employs for the haunted house and manned it behind the front desk. He makes sure everyone is rehearsed for their parts and were positioned in the right rooms of the house while keeping tabs of the employees and the cashiers, and greeting customers behind the front desk at the entrance door.

[OOC: Sebastian is working behind the front desk, so for this top-level, you can ask him questions or ask him to give a tour, etc. OTA means it's open for everyone! He also closes the house after closing time.]