Mammoth Man, by Roy Sheldon, was the first in a trio of Prehistoric Series novels published in 1952 by Hamilton & Co., and each written by H. J. Campbell.
The novel opens with Magdah blissfully working with wet clay, painting his shared bachelor man-cave (literally) walls with hunter Garo. In the course of events, they lose their slave, a sloth, and chase it into the jungle, because the daily grind simply intolerable without their sloth to perform the heavy work.
Meanwhile, far away (but not too far) Lena, a young, teenage female, is tired of the slavery she’s been force-fed since childhood by her parents, and realizes that her father is interested in mating with HER !!! (eew, gross, right?) Stealthily, she escapes. But, she’s never been on her own, had to fend for herself, or hunt for food. She eventually stumbles upon Magdah’s and Garo’s missing sloth (whom was mating in the jungle) and follows it to the man-cave.
Immediately Magdah and Lena fall for each other (love at first sight, ya know) and Garo says Lena cannot stay. Magdah insists she does. So, Garo leaves.
Shortly thereafter, a husband, wife and baby, and teenage son, enter Magdah’s lair and do battle with him, with the intent of stealing his cave. Vastly outnumbered, he is tied to a tree (see the cover art) and left to be slain by a jungle beast.
The plan goes awry when a herd of mammoths arrive, and much to Magdah’s surprise, Garo, whom departed, isn’t far away. He creeps over to see what is going on, and rescues Magdah. Together, they do battle with Yak (the leader of the invading family).
When they return to the cave to rescue Lena and face a final fight with the teenager and the hellcat woman (with baby), they find both have had their skulls smashed in by an axe! Realizing that Lena killed them, Magdah is shocked, but elated. Garo welcomes her thus as a fellow hunter-killer, and the three live together….