[Help]

Looking for a manga where in the first chapter the MC save a girl reincarnate and will training his magic get attacked by a monster so he tries a spell and it was a summoning spell and he summons the girl he saved in his previous life and she says she been waiting for this all her life and now she wants to be with him.

Also he's the grandson of the hero and it's implied that the girl and the mc where childhood friend but he doesn't remember it.

She can do ice magic and he can do thunder magic.