If you squint you can see that the onion is a trashbag, Boxjam's Kryptonite, although one assumes it is also his coat of arms. Ergo, the knight is Boxjam.
As for the "baby" part, you're on your own. Why an anachronistic medieval knight would be doing King Herod's dirty deeds us unknown to me.
From The Desk Of
"There's more to life than a little money, you know. Don't you know that? And here ya are, and it's a beautiful day. Well, I just don't understand it." Marge Gunderson