Asfr's Story is a free visual novel originally made in the NScripter engine (though my English version uses PONSCripter) by toki, the owner and sole member of the transformation group "Shinenkan." You can find their BOOTH page here (adult content warning). Asfr's Story contains no sexual content, but it has female nudity, though no actual genitalia are ever shown - the characters are smooth like Barbie dolls underneath their clothes. It should be noted that one of the characters subjected to transformation (and frequent nudity) is underaged, but again, there's no actual sexual content.

I'm Jumi (AKA JumpKain), a translator who was commissioned to translate Asfr's Story by a generous and dedicated anonymous transformation fan. I've also contacted toki and received their full blessing to release my translation.

You can find the VNDB page for Asfr's Story here.

The handsome actor Nagasaki Yuito has decided to spend his first day off in a while at a hot spring hotel deep in the mountains, together with his girlfriend Oosato Momoko and her little sister Chika. However, supernatural danger awaits them there...!