Masha. Look along the left side - artists are in red text. Also, click the link under "Source" to go straight to where the art is taken from (their Twitter feed in this case).
Because she said Young Master Bowser I like to assume this is not Bowser but Bowser. Jr's idea
And honestly, I can't choose which one I love more
Y... Young Master Bowser?Ugh... I-I understand, but I must repeat again: do not try to do anything strange!!A-a-a-are you absolutely certain you'll follow my instructions as long as I sleep with you in this form!?They had lots of sex afterwards