What appeared with the thunderclap was—
"Yes, I sensed the presence of a summoning and have arrived. Mother, Minamoto no Raikou. I make my appearance in the paradise where my child resides ♪"
Berserker, the Mother of Lightning. The strongest mystery-killer had manifested.
"SO. YOU. HAVE. COME. AS. EXPECTED. RATHER. FROM. THAT. SIDE. I. SEE."
"Yes. As per our covenant. Indeed, the bond was formed. So, like this, with a eiyah—"
"She came with enough force to smash the door the moment it opened!?"
"It's love ♥"
"Why 'love' there!? Love is scary!"
—I wasn't worried.
Because such a beautiful woman, brimming with compassion and maternal love,
"H-Mother, —"
would never abandon a new child.
"Yes, I am your mother, Rikka. ...Oh my, oh my, what is it? Won't you please leap into your mother's arms...?"
"N-No, it's not that. The Mother from London, and the Mother here are different, so... I thought I might be a bother..."
"—You truly are a gentle child, aren't you. Your mother is pleased. But it's alright, rest assured. Because—"
She smiles, a mother's smile.
"'I've etched you into my true self in the Throne.' No matter where or how I am summoned, your mother remains the same."
"—!!"
"Heehee!"
"Such a thing is trivial. To etch the existence of a child is only natural. So... yes, Rikka."
She gently opens both hands.
"'You may rely on your mother.' You are my precious, precious child, after all."
"—..."
"GO."
"!"
"ANSWER. HER. LOVE. MASTER."
The platinum mascot character declares.
"ONCE. ETCHED. INTO. THE. THRONE. YOUR. EXISTENCE. WILL. NEVER. BE. FORGOTTEN. FOR. ALL. ETERNITY."
"—Mother~~~~!!!!"
Receiving the words, Rikka embraces Raikou shamelessly and without reservation.
"I wanted to see you! I wanted to see you...! In case you didn't come, I was so scared, so anxious...! I couldn't let go of this even when I slept...!"
"Yes, you must have felt lonely, Rikka. Please forgive your mother's inadequacy."
"It's fine! As long as you came, it's fine! Ah... this!"
She offers the sword.
"No, that is your guardian sword, a precious bond that connected you and me. Your mother will be happy if you keep it."
"Really!?"
"Yes. Once you draw it, my feelings will envelop you, and you will be able to fight just as I do. Martial prowess, combat skill, strategy, tactics, just like me. You will unleash lightning at will, scatter great armies. My feelings shall utterly annihilate all that harms my daughter."
"Eh!? She's a modern Minamoto no Raikou!? Rikka-kun is!?"
"Romani, in history, Lord Raikou was male."
"THERE. IS. NO. LACK. OF. NOBLE. PHANTASM. POWER. BUT. TO. THIS. EXTENT."
—Does this mean there's no longer any concern in battle using martial arts...?
"Entrusting 'my other half' is precisely what that means. ...However, I apologize, Rikka."
She lowers her eyes apologetically.
"Truly, I wanted to give you something more delicate. I wanted to teach you housework, laundry, and the art of diligently protecting a home. But I was never able to live such a peaceful life... So, the only half-life I can entrust to you is merely this martial prowess, stained with blood and infused into this sword... Please forgive your inadequate mother..."
"Thank you."
She cuts through her mother's hesitation.
"My Mother is the kindest in Japan, and the coolest in Japan! I'm truly happy...!"
"Rikka..."
"'Thank you for becoming my Mother'!"
Rikka expresses her gratitude with a beaming smile.
"—Yes, yes. The feeling is mutual. Truly mutual..."
She embraces Rikka tightly, strongly.
"You, who are stained with blood, called me 'Mother' so sincerely... Thank you. My precious daughter, who appeared in the modern age. I will not let you be alone anymore. I, I swear to love you and love you and love you utterly."
"Nice to meet you! 'Mom'!"
"Ah, —Aahh—!"
She collapses weakly.
"Mom!?"
"Mother, Mother is too stimulated...! To be called 'Mom,' such a thing...! I'm getting excited! My body feels hot! Hot...!"
"This presence, Raikou-san! I knew you'd come, I—Whoaah!?"
With a flash of lightning, a golden blade manifests.
"KONGOSHO. IN. MASTER'S. COUNTRY. IT. IS. TAISHAKUTEN. OR. INDRA'S. BLADE. IS. IT?"
—Isn't that a Divine Construct!?
"If there's a sword, then there's a spear too. Rikka, this is how you use it—"
"Wait! Stop, Raikou-san!! That thing is seriously dangerous! Humans can't handle it!"
"Nothing is impossible for a mother and child!"
"No, it's seriously dangerous, I'm telling you—!!"
"THIS. IS. NO. LONGER. A. SUMMONING. IT. SEEMS. I. SHALL. TAKE. A. SHORT. BREAK. EVERYONE. DISPERSE. WE. WILL. REGROUP. I. WILL. SEND. OUT. A. RECALL."
"Let go, Kintoki! Why, why do you interfere with my love for my daughter—!"
"Now! Seriously, bear with it now! Quickly! Get Rikka somewhere else!!"
"MASTER. LEND. ME. YOUR. SWORD. I. SHALL. ENSURE. YOUR. MOTHER. CAN. REMAIN. EVEN. AFTER. HUMANITY'S. RESTORATION."
"Really!?"
"NOTHING. IS. IMPOSSIBLE. FOR. THE. GORGEOUS. NO. IMPOSSIBILITY. EXISTS. FOR. THE. GORGEOUS. ON. EARTH. ALL. RULES. OF. ALL. CREATION. ARE. ME. I. AM. THE. RULE. Fuhahahahaha!! Mph, no, my cloak has come undone."
"Yay!! I'm with Mom—!!"
—After that, everyone cleaned up together.
Doujikiri Yasutsuna
One of the Five Great Swords of Japan, imbued with a mother's feelings. A famous sword entrusted to Rikka.
It is imbued with a maternal love reaching the point of motherly madness. Once drawn, it becomes a blade that annihilates all that harms her child.
It grants martial prowess A+ equal to Raikou (physical burden disregarded), and the ability to convert her own magical energy into lightning, gaining Mana Burst (Lightning).
Having slain countless mysteries, its cutting power is several grades higher against Earth attributes and demonic entities.
However, maternal love equals madness.
Unless one is a "vessel that can accept her love," they will immediately be swallowed by a mother's love, their personality rewritten, becoming a possession that blindly worships the mother.
If the heart does not possess a darkness or light appropriate for the love given, it can become a sword that kills everything of the child. Did Raikou understand this—
Only she knows.
"Boooooo!!!"
"Hoh, a golden one. You inadvertently wished for the form of the god Medjed, did you not? I must commend your keen insight! For he is quite a great god!"
"Th-That's, f-forgive me, sacrilegious...!"
"Hoh, the god of the sky, finally speaking his mind to the Golden King! Good! I permit it! Go forth! Like the flapping of Horus's wings! (grab!)"
"Please forgive me, please forgive me, please forgive me, please forgive me, please forgive me, please forgive me, please forgive me, please forgive me, please forgive me, Pharaoh!!!!"
"Achoo!!"
—Achoo!