I got a new sales job recently (3 months) in a field that I'm really enjoying. For the most part it's been great, and I'm on course to win the sales competition we have every month for July. I've also been given a key to the shop and more responsibility by management so you could say that things are going, well.

However there's a problem.

Shortly after I was hired, this chick was hired to replace another member of the team that was let go. When she first came on board she was nice enough that myself and other co-workers took a real liking to her. She's also very over-weight so there was no attraction to her (which in my mind made working with her a lot easier). However recently I've started to notice certain aspects of her behavior which make me very cautious about her.

First is how much management have warmed up to her. In the actual shop, and as part of operations, there are tasks that are supposed to be done by every member of the team. These tasks rotate between team members. However she often gets out of doing these tasks by offering to do other tasks (that are often unnecessary) or by claiming that she feels 'unsafe' even though the risks faced are the same for all of us.

Second, she also has a side hustle which she has somehow got the owner of the shop to support even though his business itself cannot legally (prohibited by law) or feasibly (direct competition) take on. Third, she also has a way of assuming authority when none has been given. For example, a few nights ago it was her and myself closing the shop. I technically have seniority however she tried multiple times to 'tell me what to do'. I did what I thought was necessary to do when she did, but ignored those things I thought were not, all the while keeping my mouth shut and observing her behavior.

My thoughts on her are that she's proving to be more of a threat as time passes by. I also feel that she's talking to management about myself and other co-workers about stuff that she notices (without telling us). This is a suspicion both myself and another co-worker have. To me, her ingratiating and calculating behavior tells me that I need to watch out for her. I also feel that I need to get the upper hand on her somehow in the event that a decision needs to be made on who between her and myself, is promoted in future. Has anyone ever had an experience like this before?