It's a jam I strictly entered on the forums, I do know that as of late they've had itch.io jam pages for it now--but I do not think I had an itch.io account at the time, so I entered it like most others do by making a WiP thread in the NaNoRenO board since the jam's been going on annually I think before itch.io even started so a lot of us enter it that way, some even have surprise entries by posting a complete game made within the time-span they never announced. But I did announce mine.
This was my entry thread in question; https://lemmasoft.renai.us/forums/viewtopic.php?f=50&t=42807
And in the pinned topic, "NaNo 2017 Games by Genre", which shows every game--finished or not--entered into the jam by genre to their WiPs, you'll find mine "An Encounter ~In The Rain~" by the genres "Friendship" and "Linear"; https://lemmasoft.renai.us/forums/viewtopic.php?f=50&t=42982