because i've played thru the prince route several times and i still only have 1 CG.

Are they sometimes dependant on the jobs??

Also i've played the bad boy route so many times and im still missing the first CG. I have no idea what that CG requires me to do and its driving me nuts

I've now gotten all the Prince CGs, but i have no idea how to get the first Bad Boy CG. It's so frustrating and i have no idea what im doing wrong

I don't think the job matters that much as long a the MC and BF have to  keep  their jobs, (base bf automatically loses his job though) To get the Bad Boy bf I think you have to get the scene where they burn the MC's ex's belongings in order to get the first illustration. 

Edit I take that back about the Bad BF I'm not sure if there's an illustration there or not

I figured it out. You have to (try to) reject him when hiding from the cops after he shows you the graffiti he did. I still don't know how to get 3 of the achievements tho. I kinda hate the concept of hidden achievements because of that.

I've found two of the hidden achievements I was missing, and I'm about to move onto the last one I needed. In the Flirt boyfriend route, you need to max out the Sexiness stat. For the prince, you need to max out the intelligence stat. Following the same trend, the Bad Boy boyfriend's equivalent achievement most likely requires you to max out the attitude stat.
These are all bad endings, which is super interesting. I think playing on Easy mode prevents the scenes that maxing out the specific stats trigger, so you'll need to play on Normal or Hard.

Edit: For the bad boy's hidden achievement, you actually need to max out the Anger stat.
Second Edit: By achievements, I mean the ones in the Steam version. I forgot to mention that.