Kyoko leans on your knee stupefied, admiring your imposing nude body. By the time she finds her words she is overcome by thrill. "This is marvelous... please, Nayuki-san, make me as big as you", she says, her eyes gleaming. "My pleasure", you say with a warm smile, as you begin picturing her as large as you; growth ensues. "Wah~! What a funny sensation", she giggles as her body expands. At 2.35 metres tall she sticks her chest out, bursting out of her swimsuit; she is noticeably aroused. You help her, increasing the growth speed; in a few seconds she doubles in size - and rising, soon overtaking you.
"It's not like you dislike it, do you?", you giggle, standing up. "Dislike it? This is the best thing that has ever happened to me! I always dreamed growing into a giantess" she replies ecstatic, and hugs you into her bosom; you can feel her boobs swelling together with her body. You shoot her up a few more metres, allowing you to breath, resuming the process. "Are you enlarging me further, Nayuki-san? No... it's not like I don't want you to, I'm glad. Please keep it going!" she says frolicly. "Well, since you're enjoying it that much, I'll just keep growing you until you say stop. And I'm growing with you!" you say withg a grin, immediately catching her up.
Your bodies surge with grow; you're picturing yourselves as big as skycrapers, and the ride is going to be an enjoyable one. At 30 metres and growing, you walk into ground as the onsen is becoming too small for the both of you, even if you're standing. Kyoko's large boobs hang upon the onsen house as she kneels before it. The owner, startled by the girls' booming giggles, looks in awe at her voluptuous expanding body as he leaves the house, few less than a mere model house from her perspective.
Meanwhile, you feel like walking into the nearby woods, and call Kyoko; she soon joins you, still looking back at the miniature onsen with a smile. You advance through the woods, trees coming down to your diaphragm, your waist, your crotch (Kyoko looked clearly aroused from the friction)... all this happens rapidly as soon you are out of the woods. Stepping over a road, you walk into a valley. "Hmmm... what a nice place!" you say at 67 meters tall, stretching out.