Im surprised she trust more that dude than her own son, she is never suspicious about any of his actions, also the MC never told his mom about how her BF was sending him pics of her because he wanted her to be happy with her relationship i think lmao.
I can only imagine the aftermath to be about the Gyaru dude being actually a good father figure and the MC becoming an actual pervert stalking her mom's new life. I would be surprise if isnt that or she just keeps her son as her NTR plaything.
Speaking of art, pag10 is probably my favourite scene in this chapter.