Chitoge was always going to be confirmed as a 'promise girl'. It was already heavily hinted at when she recalled the 'Zawsze in Love' thing that was essentially a callback to the very first chapter and the setup for the 'promise' premise. I dunno what you're expecting. It's primarily a romcom/dramedy with a central mystery, so there's going to be a lot of talking and a lot of flashbacks and investigating the past. The 'mystery' isn't in the tags, but it most definitely is covered in the summary, and so is the fact that more girls were involved in his past and the pendant. It's like the tools to know what kind of story is being told here are right there on the main page for this manga on this site. Reader's own fault if they didn't know going in.
So yeah, anyway, Chitoge now has to come to grips with the fact that Raku is most likely the boy she met 10 years ago. Same for Kosaki and her own remembered promise. And there's yet one more girl we haven't met so at this time involved in the events of 10 years ago... And I've said it before, but I really despise her so damn much. I actually like Chitoge for being a decent person other than her treatment of Raku (which is partly his own damn fault for not accepting her apologies and being so bull-headed with her in general- they both are too damn stubborn, but they're softening), and obviously Kosaki is very nice (but too shy and reserved for her own good), but the last girl, Marika... she really bothers me. There's like something seriously wrong with her, like 'major screws loose' wrong. You'll see when she's introduced.
Also Seishirou is actually really sweet under all that 'tough girl' act.