The book appears to be unironic non-fiction, judging by the Table of Contents.
Originally published by Saucerian Books in 1959 as From Outer Space to You. Remarkably similar to George Adamski’s narrative (first published in 1953’s Flying Saucers Have Landed), Howard Menger claimed to have been contacted by morally, intellectually, spiritually, and technologically superior “space people,” many of them appearing as strikingly beautiful women, beginning in 1932 at age ten:
There, sitting on a rock by the brook, was the most exquisite woman my young eyes had ever beheld!
The warm sunlight caught the highlights of her long golden hair as it cascaded around her face and shoulders. The curves of her lovely body were delicately contoured—revealed through the translucent material of clothing which reminded me of the habit of skiers.
Starting in 1956, Menger relates taking journeys in various spaceships, eventually traveling to the Moon and Venus, both of which he describes as having an oxygen atmosphere, lush vegetation, native settlements, and so on. You can hear an interesting NBC interview with Howard and Connie Menger—from the First Interplanetary Spacecraft Convention at the Menger farm, 1958—at archive.org.