Fukasaku

When pushed to the limit of his abilities, Jiraiya can summon these two elder toads, Ma and Pa, onto his shoulders to enter a form called Sage Mode. Despite Jiraya being an elder himself, he speaks to them quite respectfully, while they refer to him as "Jiraiya-chan" or "Kiddo". It is known that Pa's name is Fukasaku, though his wife's name is unknown. During the flashback of Jiraiya's visit to the Toad Sage, it is seen that both of them sit on each side of the Toad Sage. Ma seems to constantly bicker with the Toad Sage for being senile, while Pa seems to advise him, and just try to help him out.

Personality
Both toads are considered old and wise and are greatly respected by all who know them well enough. However, in reality, like it would seem, they are both acting towards each other like an old married couple, like they are, and constantly bicker over all the small things while they should take focus on the bigger picture, as seen when they were summoned and Ma began complaining about the fact that they were going to be there all night and miss dinner. It would seem that only Pa can remain serious in even the worst situation, while Ma will constantly find a way to bicker with Pa, and at the same time does not have enough respect for the oldest and greatest of all toads, constantly calling him senile for constantly forgetting everything.

Infiltration of Amegakure
When Jiraiya began to lose his battle with Pain, he called the aid of Ma and Pa to help him. With the two toads he transformed into his Sage Mode and began to battle the three bodies of Pain on seemingly equal terms. Unfortunately after the Toad Sennin used their genjutsu and Jiraiya killed the three bodies, Pain's remaining three bodies arrived and turn the tables in the battle. After Jiraiya managed to kill one of the bodies, he had Ma take the body back to Konoha so Tsunade could study it. After she left, the battle took a tragic turn as Jiraiya was attacked by the five remaining bodies, being pierced right through his back by five pike like weapons. Jiraiya knowing his end was near, carved an encrypted message onto Pa's back allowing him to escape, while Jiraiya succumbed to his injuries.

Post Hunt for Uchiha Arc
After the 8-Man Squad failed mission to find Itachi or Sasuke Uchiha Pa remained in Konoha to inform his student's student Naruto Uzumaki that Jiraiya died in battle. He apparently has taken a liking to Naruto and hopes he really is the "Prophesized One" who would save, not destroy the world. Pa offered to train Naruto in the sage arts, so that the boy could stand a chance against Pain, and Naruto readily accepted.

Sage Arts Training
After Naruto got ready to go, Pa took out the Toad Summoning scroll, which was easily recognized by Naruto. The two then traveled to Myobokuzan through a reverse summon by Gamakichi. Pa then teaches Naruto about sage chakra. To learn sage techniques, you have to become one with nature. After Naruto asks how to do that, Gamakichi tells him he has to die. Pa tells Gamakichi to stop it and after telling Naruto that he doesn't have to die, he leads them to a waterfall which will make Naruto's training easier. The waterfall is filled with toad oil from the Myobokuzan Mountain. He puts some on Naruto's hand and explains that the oil will help him use natural energy. He then explains that if you don't use enough natural energy it won't work. And if you use too much natural energy, you'll turn into a frog. Since Naruto is using too much energy, he turns into a frog, which he panics about. After Naruto turns back to normal(with a hit from Pa's staff), Pa tells him that not even Jiraiya could control the natural energy the first time, and would turn into a frog. He then reveals that all the stone frog statues behind them are the past failures who couldn't control the energy. Naruto says his way will be like the "pervy sage's"(Jiraiya) and that he won't give up. Pa is glad to hear it. After Naruto gets a little natural energy, Pa tells him to lift the stone frog statue with his normal chakra, but the stone won't budge. Pa tells him to lift it again with his sage chakra, and it is a success. Pa then remarks that Naruto is getting the hang of this faster than Jiraiya did, but after seeing Naruto almost drop the statue says that he's more foolish than Jiraiya too.

Abilities
In battle, they are quite formidable. Ma is shown to summon a serpent like creature from her stomach and to be capable of breathing fire, and Pa can create huge gusts of wind as well as firing jets of water so concentrated and so fast that they can cut through solid stone. Combined with Jiraiya's ability to spit oil, these abilities create a huge inferno, though it's capabilities are unknown, because the attack had never successfully struck the target. Also, they seem to be very intelligent, as they quickly determine a weakness in the way Pain uses his Rinnegan.

The two toads are also capable of very powerful genjutsu, by means of singing. This ability cancels out Jiraiya's lack of aptitude for genjutsu, making the combination that much stronger. However this Genjutsu takes time, and in order to use, both Ma and Pa must adjust their voices tones and harmony with one another, something neither of them seems happy about doing. When finally applied it attacks the opponent's sense of hearing and will completely paralyze the nerves and thus the entire body of the target(s). However it gives Ma and Pa and sore throat which in turn means that using it, will be a one shot technique.

Also, Pa has at least been confirmed to be able to use Senjutsu, a technique that gathers the natural energy around that person and grants him a high amount of chakra, and an unnaturally high level of raw strength.

Quotes

 * "By the way kid, didn't you say you hated this form, because you think it would scare the girls away?"
 * "You know Jiraiya-chan, it is high time you learned how to activate Sennin Mode yourself."
 * "Hahaha... pervy sage. That fits Jiraiya to a T."