PHOTO AT THIS LINK: Spencer Wihelm Willis
Pic is of alternative Spencer
Spencer Willis is one of the seniors of Hanover House, and seen with Justin Bancroft being one of his friends. They have known each other since freshman year. He's tall, with dark brown hair and brown eyes.
Justin implies that Spencer has a powerful father in the military (Marines), and this is probably also the reason why Spencer is to be sent to West Point after Dalton. From what is known about Spencer, he's a little more rambunctious than Justin is, described as devil-may-care, and is usually at Justin's wing along with the Junior (and presumably prefect-to-be) Danny Abbot.
According to this side-canon story, Spencer has been, for quite a while, the object of Merril Portman's unrequited affections, or so she believes. He is one of the first people to welcome Merril into Hanover in the Hanover side-canon backstory,A Rainy Story.
The illusions of unrequited affections persisted until this second part to the side-canon appeared, revealing that Merril had misheard, and that Spencer did like her and would very much like to go to prom with her. It is a spectacular depiction of Spencer's own wild moments, which is apparently characteristic to him.