Ai-kun is a small, fluffy creature with emerald-colored fur, a red, jewel-like mark on its forehead, and a long, bushy tail. It belongs to Ranka Lee, who found it wandering alone on Island 1 of the Macross Frontier fleet and adopted it as a pet, unaware that it is actually a larval form of the Vajra, an alien species humanity is at war with. Small enough to be held in one’s hands, Ai-kun often hides under Ranka’s clothing or nestles in her hair. Its name comes from the word “Aimo,” a song with deep connections to the Vajra. Ai-kun is affectionate, gentle, and fiercely loyal to Ranka, staying by her side even when she is in danger. It emits a soft light in response to Ranka’s singing. As the story progresses, Ai-kun develops the ability to generate a protective fold barrier, which it uses to save Sheryl Nome from the vacuum of space. It eventually grows into a larger, more mature Vajra with wings on its back, but its core personality and devotion to Ranka remain unchanged. Through its bond with Ranka, Ai-kun serves as a living bridge between humans and the Vajra, revealing that the alien species is not mindlessly hostile.