Tensei Shitara, Shurabadeshita. Zensei Kara Teita Saikyo No Motokano Tachi to No Dokyo Seikatsu (MF Bunko J) [Light Novel]

[Machine Translation] I, Allen, who had been living in poverty, was rescued from a difficult situation by "I finally met you...". I'm here...! It's me... It's Hershy! It was the alchemist girl who had been waiting for me for 800 years. I don't remember her, but it seems she was my love in a previous life. I'm not sure if it's a good idea to go to the beach. I promise you that I will not leave you alone this time..." I was about to take her hand when... Wait a minute. I'm not the only one waiting for you! A princess knight, a spirit girl, and a machine girl. They all knew about my previous lives, and they all told me that the world would be destroyed if I did not regain my memories of the past...? A heart-warming drama filled with ex-girlfriends from previous lives, two previous lives, two previous lives, and two previous lives is about to begin!

貧乏ながら生き永らえてきた僕、アレンの窮地を救ったのは、「やっと、会えた...っ!私です...ハーシィですっ!」八百年間、僕のことだけを待ち続けていたと言う錬金術師の女の子だった。僕は憶えていないけれど前世の想い人らしい。「うん、約束するよ。今度は君を一人には―」覚悟を決め、彼女の手を取ろうとしたその時...え、ちょっと待って。僕を待っていたのは一人じゃない!?姫騎士、精霊娘、機械娘。立て続けに現れた彼女たちは皆、僕の各前世を知っていて、おまけに僕がかつての記憶を取り戻せないと世界が滅ぶって...!?前世、前々世、前々々世、前々々々世の元カノたちで溢れたハートフル修羅場が今、始まる!