OpenTGC review
OpenTGC hosts short captions and longer stories. Its guide describes two choices that matter for longer reading. Authors can join their posts into a numbered series and decide which of those posts readers can save outside the site.
Find the order of a serial
The guide says a series shows the part number, a list of available parts and previous and next links. Signed-in readers get a Continue your series section for the runs they’ve started. The Reader has separate views for recent posts, follows and private saves. OpenTGC’s rules prohibit material involving minors and unauthorized reposts. The terms give it a non-exclusive license to host user contributions.

The author controls the download button
OpenTGC gives contributors a download setting for each post. When downloads are enabled, readers can save HTML or use the print view to save a PDF, including while signed out. XStory reserves PDF and EPUB export for Premium. With OpenTGC, check the specific chapters you want to keep.
Anabel’s take
I'd open the series list first to see the order and then check the download control on the parts I wanted to take along. For a single short caption, a saved post would be enough.