As for the male rivals in Transformers Prime and Transformers Animated are quite simple and complicated. For example, Seekers are very protective and sometimes flirty when they see other seekers or females seekers, even seekerlings. At the top of list that is easy enough to eliminate is Starscream.

In Transformers Prime, Starscream will flirt will both Info-chan and Yandere-chan, if Bumblebee were to see this happen, he will try to protect Yandere-chan from harm. In Transformers Animated, Starscream WON'T flirt with Yandere-chan, instead, he will find her injured and take care of her and protect her from Megatron's wrath.

Next to Starscream will be Knockout. Knockout hasn't been mentioned in Transfromers Animated, so in Transformers Prime, Knockout will flirt with Yandere-chan all the time even in battle. 

Third is Breakdown.

Breakdown will flirt a little with Info-chan and Yandere-chan. In the episode, Dues Ex Machina, Breakdown will battle against Yandere-chan when he tosses Bulkhead away. Even if Yandere-chan couldn't win she'll try her best to fight with her knives.

Fourth is Lockdown.

Lockdown the bounty hunter does tend to flirt with girls and calls them sweetspark, BUT if he hurts Bumblebee, Yandere-chan goes protective of Bumblebee and go aggressive mode. So Lockdown won't stand a chance against her.

Fifth is Steeljaw.

Steeljaw tried to flirt with Strongarm in the show so he will flirt with Yandere-chan but she will fight him but lose as he kissed her. In order for Yandere-chan to escape the cons base is to release a smoke bomb. That will result in a mini-game for her to make her escape. If she doesn't make her escape in time, Steeljaw will make her prisoner in his base.

I hope you like the chapter of the male rivals. Pretty soon I'll make some changes and add in some characters from Yandere Simulator. Leave a comment of which male rival I should put in.