For anyone who is wondering why the chapters are so slow to update, correct me if I'm wrong on this, but the scan team that was was working on this has disbanded (or just dropped this series) and that's why we won't be seeing anymore updates unless someone else picks it up. The same team was also working on JunJou Romantica, and they're no longer working on that either (but one team member has decided to continue working on it by themself so it may take longer than usual to see updates since it's just one person).
Fortunately, Sekaiichi Hatsukoi has an official translation thanks to SuBLime. They translate a whole bunch of yaoi series, so I definitely recommend checking out their catalog if you are able to purchase manga.
JunJou Romantica also got an official translation, too, by BLU (JunJou Romantica was named JunJo Romance/Pure Love under BLU), but it got dropped after 12 volumes because BLU was owned by Tokyopop, and at that time Tokyopop had gone under (hence why it got dropped). I know it makes me super sad too. I really hope SuBLime or some other publisher picks it up so we can get an official translation once again.
For anyone who is wondering why the chapters are so slow to update, correct me if I'm wrong on this, but the scan team that was was working on this has disbanded (or just dropped this series) and that's why we won't be seeing anymore updates unless someone else picks it up. The same team was also working on JunJou Romantica, and they're no longer working on that either (but one team member has decided to continue working on it by themself so it may take longer than usual to see updates since it's just one person).
Fortunately, Sekaiichi Hatsukoi has an official translation thanks to SuBLime. They translate a whole bunch of yaoi series, so I definitely recommend checking out their catalog if you are able to purchase manga.
Here is the link for Sekaiichi Hatsukoi on their website (it's under the English name: The World's Greatest First Love):
https://www.sublimemanga.com/world-s-greatest-first-love
JunJou Romantica also got an official translation, too, by BLU (JunJou Romantica was named JunJo Romance/Pure Love under BLU), but it got dropped after 12 volumes because BLU was owned by Tokyopop, and at that time Tokyopop had gone under (hence why it got dropped). I know it makes me super sad too. I really hope SuBLime or some other publisher picks it up so we can get an official translation once again.