A: He drew out his penis, Ma'am. Q: After he drew out his penis, what happened? A: He inserted his penis into my private part, Ma'am.[17] Further, "AAA" testified that on September 28, 2005, while she was asleep, she felt someone touching her vagina. Upon opening her eyes, "AAA" saw that it was Padlan who was touching her vagina.[18] As shown by "AAA's" testimony, she was able to narrate in a clear and candid manner how Padlan raped and molested her. Being a 9-year old rape victim, her testimony deserves full weight and credence. "[A] girl of tender years, who barely understands sex and sexuality, is unlikely to impute to any man a crime so serious as rape, if what she claims is not true."[19] Moreover, the defense did not present any improper motive on "AAA" why she would impute a serious charge of rape against Padlan. Verily, we affirm the CA that all the elements of Rape and Acts of Lasciviousness had been proven in the case at bar. Besides, the RTC found that "AAA's" testimony was credible since it was given in a categorical, straightforward, spontaneous, and frank manner despite her young age.[20] We find no compelling reason to deviate from these findings especially since the CA affirmed the same. The finding of credibility should not be overturned since the trial court judge had the opportunity to personally examine the demeanor of the witnesses when they testified on the stand. The finding of credibility may be overturned only when certain facts or circumstances are overlooked, misunderstood, or misapplied, and the same could have materially affected the outcome of the case. No such circumstance is present in the case at bar. Thus, the finding for "AAA's" credibility stands. For his defense, Padlan denied the charges against him and presented an alibi. He contended that on the dates when the rape and acts of lasciviousness were alleged to have been committed, he was either in Nueva Ecija buying vegetables for resale in Bulacan, collecting payments from his buyers at the market and resting at home thereafter, or watching television at home. These are all uncorroborated selfserving statements. Time and again, the Court has held that denial and alibi are inherently weak defenses that cannot prevail over the positive and categorical testimony and identification of the complainant.[21] Moreover, for alibi to prosper, it is insufficient that the accused prove that he was somewhere else when the crime was committed; he must likewise establish that it was physically impossible for him to have been present at the scene of the crime at the time of its commission. In this case, while Padlan alleged that on August 7, 2005 he was in Nueva Ecija with his employer buying vegetables, Padlan failed to present the testimony of such employer. Consequently, his claim remained uncorroborated and unsubstantiated. As such, in the face of the accusation against him, his alibi cannot prevail over the