It was displayed on the second floor of a home near Cramer & Locust on Thursday.
Neighbors complained to the UW-Milwaukee's Neighborhood Relations Department when they spotted it.
Bradley Jayhan-Little, who lives nearby, said the sign was the latest example of student renters disrespecting the area's homeowners.
"That disrespectful culture was encapsulated in that banner," he said.
Jayhan-Little considers the banner offensive. He said it promotes sexual assault.
According to Keri Duce, Director of External Relations at UW-Milwaukee, the Neighborhood Relations Department is responsible for maintaining positive relationships between the university and nearby homeowners/residents.
"We have close ties with the area neighborhood associations, we work with the city, and we have a variety of partners there," Duce said.
She said police were called on Thursday after residents complained. The responding officer recommended to the people living in the home that they remove the banner.
The residents told TODAY'S TMJ4 they were excited that this week is "welcome week" at UW-Milwaukee and were just trying to be funny.
They said they removed the banner immediately upon getting the visit from campus police.
Duce would not confirm or deny that the house's residents are students. But she said UWM students can still face sanctions for offenses committed off of campus.
Complaints can lead to a student having a hearing, or at a minimum, a meeting with the Dean of Students.
Duce said sanctions are then determined on a case-by-case basis to fit the offense.
"As an example, if a student gets an underage alcohol ticket, we have an alcohol education class they go to," Duce said.
Jayhan-Little said he hopes his neighbors realize the banner was offensive to some of the people in the neighborhood.
"I hope they take a moment to ask themselves the question about why other people took issue with this," he said.