The name Sincere Love in Chinese / Japanese...

至愛 can mean the best love or most sincere love of your life.

This could be a romantic love such as your love for your spouse or a boyfriend/girlfriend.

It can also apply to the extreme love you have for your children or a parent and maybe a really good friend.

See Also:  I Love You

最愛 is a Japanese word that means the best love, beloved, or most sincere love of your life.

This could be a romantic love such as your love for your spouse or a boyfriend/girlfriend.

It can also apply to the extreme love you have for your children or a parent and maybe a really good friend.

四拳波羅蜜大光明 is “shiken haramitsu daikōmyō,” a famous Japanese Buddhist mantra.

四拳 = shi-ken = four fists (many translate this as “four hearts”).
波羅蜜 = ha-ra-mitsu = A loanword representing pāramitā, or entrance into Nirvana. Awkwardly, it also means jackfruit.
大光明 = dai-kou-myo = big/great light bright (great bright light).

Shiken represents four hearts:
1. The Merciful Heart - Love and caring for all living things.
2. The Sincere Heart - Pursues righteousness, or the right path - sincerely trying to do what is right.
3. The Attuned Heart - Knows that nature and fate have their ways, and thus stay in tune with the universe.
4. The Dedicated Heart - Steadfast on the chosen path to the end.

真誠 is the true essence of sincerity.

It takes strength of personality to be truly sincere without overdoing it. Speaking of strength, this is probably the strongest way to convey the idea of sincerity in the Chinese language.

The first character literally means true, real, and genuine. While the second character means sincere and honest.

See Also:  Love | Honor

While 真心 literally reads as “true heart” or “genuine heart,” the understood meaning is sincerity, devotion, sincere, or heartfelt. Some will extend the meaning to be like “true love.” It's the idea of doing something or treating someone with genuine feelings.

真心 is valid and has the same meaning in both Chinese characters and Japanese Kanji.

Note: While not too common, this can be the female given name “Mami” in Japanese.

屋烏の愛 is a Japanese way to express true love or deep love.

The phrase literally suggests that this is a love for someone so strong that it can reach a crow perched on that person's roof.