As you can see in some of these I explored with a very minimal color pallet mainly consisting of black on a colored background and sometimes with hints of additional color and this gives them a more graphic look as opposed to being purely illustrative, I quite like these and i'll keep on exploring this as long as the idea is suitable for it:
Single

Geek

Control Freak

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Some of my favorites, I think I did a good job illustrating these and conveying the concept I had in mind so yeah, really happy with them:
Coffee-holic

Homeless

End of the line

Moody

Innocence

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And here are a few more concepts I illustrated:
Love Notes

Smoker

Family

Toxic Union

Sugar Rush

I hope you enjoyed them. :o)