We don't much remember that Freyr, the Norse god of harvest, also had the unique property that women couldn't be harmed near him. Not because he would attack those who wanted them harm, but because it was like a magic shield was put on them. Weapons would literally break on impact with women's skin if he was around.
Gerd is the only jotun woman romantically involved with the gods who is consistently depicted as big, and often fat. That's because in the story about Freyr falling in love with her he especially admires her "big, white arms". It also makes sense that a god of harvest and plenty would love a woman embodying that.
Freyr, his sister Freya and their father Njord (who also married a jotun btw) are all gods of fertility in each their own way, so I like to depict them as overweight too, though not as big as Gerd.
I also like depicting Freyr as something of a classic romantic hero because of how hopelessly and dramatically he falls in love with Gerd. He longs for her and cries when he thinks he can't be with her, and gets depressed because he has to wait a whole week to meet her in person. Also, the reason why he doesn't have a sword is because he gave it to Gerd as a present.
And Gerd is a tough lady. Freyr's servant threaten her with death (without Freyr knowing) and she doesn't give a shit. He had to threatened her with bad luck for the rest of her life before she agreed to meet Freyr.
Her father is the sea jotun Ægir which is why I tend to give her a sea inspired look.