援助交际起源于20世纪90年代的日本，社会上普遍简称其为“援交”，最初指在利益驱使下女性与男性约会的正常交际行为，但在发展过程中，援助交际伴随着大量性服务的出现，最终成为少女卖淫的代名词。虽然目前援助交际参与者范围已经从女中学生扩展到了女大学生、护士、上班族、家庭主妇甚至男性等人群，但本文的研究主体仅限未成年女性。援助交际发展到今天演变出许多新形式，如邂逅咖啡厅、JK经济等，但是性交易色彩却越来越明显，并且呈低龄化发展趋势。援助交际存在以下三个基本特征：第一是自主性，援助交际行为是在自主自愿的基础上进行的交际活动；第二是兼职性，参与援助交际的少女只是将援交行为当作是赚取零花钱的兼职工作，并没有职业卖淫的打算；第三是交往性，是基于双方合意进行双向情感互动的交往行为。尽管经过了30多年的发展演变，但日本社会一直未能形成对援助交际的统一认知。日本社会大众与学界对援助交际的定义有所不同，社会大众将援助交际简单定义为卖淫，日本学术界探讨的定义更加严谨，将援助交际定义为包含性服务内容的性交际行为，形式上大致可以分为普通交际和性交际两种，其中，普通交际不涉及性服务，只是通过约会、聊天等交际行为获得金钱利益，性交际则涉及到了性服务交易。

在日本，由于援助交际现象由来已久，其已经针对未成年援助交际制定了多部法律，进行了多层次、多方面的规制。我国对日本援助交际法律规制方面的研究较少，目前还没有对日本援助交际法律体系进行系统的整理、论述。本文系统的整理了日本法律体系中涉及到援助交际的相关规定，并将相关法律从一般法、儿童保护法、专门立法三个层面进行详细梳理。在一般法层面上，日本通过《刑法典》中的强奸罪、强制猥亵罪和劝诱淫行罪对不满十三周岁的未成年人援助交际的行为进行规制，除此之外，配套以《卖春防止法》加强对卖淫嫖娼行为的禁止和打击力度。在儿童立法层面上，通过《买春儿童、儿童色情处罚法》中的买春儿童罪、买春儿童斡旋、劝诱罪，对与十三到十八周岁的儿童进行性交易的行为加大处罚力度，严厉惩戒买春儿童的行为。除此之外，《儿童福祉法》和《青少年保护育成条例》也包含禁止儿童淫行行为的内容。在其他专门立法中，《风俗营业的规制与业务适正化法》总体上对风俗业的营业准则进行规定，禁止未成年人通过性风化场所从事援助交际。另外还有《交友网站限制法》和《不良网站对策法》对网络环境进行监管，防止援助交际通过网络手段发展蔓延。

虽然日本规制援助交际的法律法规数量较多、涵盖面广，但并未发挥出十分预期的规制效果，主要原因有三：一是援助交际的性质存在争议，是否应当将援助交际当作儿童卖春处理还有待商榷；二是规制援助交际行为的法律存在冲突，不同法律对援助交际的认定不明确，并且适用不同的法律会得到不同的量刑结果，不利于司法公正；三是由于援助交际的私事属性造成取证困难，因此，司法实践中存在警察钓鱼执法行为，违反法律的道德正当性，造成法治风险。

反思日本援助交际法律规制，主要存在以下三个方面的问题。第一，被害描述中“主体性”建构缺失，限制未成年人的性自愿，将其构建成被害人，忽视了未成年人的主体性；第二，援助交际“犯罪化”的法理依据不足，杜绝一切外力干扰是否就能实现儿童的最大利益值得商榷；第三，“非行少年”标签阻碍法益保护，对未成年人进行收容教育，贴上“性过错”的标签，可能会对其造成二次伤害。我国也存着未成年人的援助交际行为，反思日本援助交际法律规制的相关问题，得出以下三点启示：一是要尊重未成年人性权利，明确援助交际的法律性质；二是审慎对待援助交际犯罪化，要注重预防，完善社会保障和救助机制，帮助从事援助交际的未成年人重新融入社会，避免其走上职业卖淫的道路；三是警惕越轨少年的标签效应，避免被标签的未成年人失学失业，成立专业的未成年人保护机构，保障其升学、就业的权利，加强心理引导，保障他们获得公正的待遇，回归正常生活。

Enjo-kōsai originated in Japan in the 1990s and is commonly referred to as "compensated dating" in society. Initially, it referred to the normal social interaction between women and men driven by financial interests. However, as it evolved, enjo-kōsai became synonymous with teenage prostitution, involving a significant amount of sexual services. While the range of participants in enjo-kōsai has expanded to include female university students, nurses, office workers, housewives, and even males, this research focuses exclusively on underage girls. Despite over 30 years of development and evolution, Japanese society has failed to establish a unified understanding of enjo-kōsai. The general public views enjo-kōsai simply as prostitution, while the academic community in Japan explores a more rigorous definition, categorizing it as sexual interaction that includes sexual service transactions. It can be broadly categorized into two forms: non-sexual interaction and sexual intercourse, with the former involving activities such as dating and chatting for financial gain, and the latter involving sexual service transactions. Enjo-kōsai has evolved into various new forms, such as encounter cafes and JK businesses, but the emphasis on sexual transactions has become more prominent, with a concerning trend of involving younger individuals. Enjo-kōsai is characterized by autonomy, as it is a communicative activity based on voluntary and mutually consenting emotional interactions. It is also characterized by part-time involvement, where teenage girls perceive enjo-kōsai as a part-time job for earning pocket money without intending to pursue a career in prostitution. Additionally, enjo-kōsai involves social interaction based on mutual agreement and emotional exchanges between both parties.

In Japan, due to the long-standing phenomenon of enjo kosai, a number of laws have been established to regulate underage prostitution. At the general legal level, Japan regulates the behavior of minors under the age of thirteen who engage in enjo kosai through criminal laws such as rape, forcible indecency, and solicitation of minors for immoral purposes, and the Anti-Prostitution Law to strengthen the prohibition and crackdown on prostitution. At the legislative level for children, the punishment for buying or inducing children between the ages of thirteen and eighteen to engage in sexual transactions is intensified through laws such as the Law on Punishing Acts Related to Child Prostitution and Child Pornography, which includes offenses such as purchasing or arranging sexual encounters with children. Additionally, the Child Welfare Law and Youth Protection and Development Ordinance also include provisions prohibiting child prostitution. In other specialized legislation, the Law Regulating Adult Entertainment Businesses sets guidelines for the operation of the sex industry, prohibiting minors from engaging in enjo kosai at sexual establishments. Furthermore, the Internet Dating Site Regulation Law and the Act on the Regulation of Harmful Websites regulate the online environment to prevent the spread of enjo kosai through online means.

Although Japan has numerous laws and regulations governing enjo-kōsai, they have not proven to be highly effective in regulating the phenomenon. There are three main reasons for this: First, there is controversy surrounding the nature of enjo-kōsai, and whether it should be treated as child prostitution is still a subject of debate. Second, the laws regulating enjo-kōsai are conflicting, with different legal definitions and varying sentencing outcomes depending on the specific laws applied, which undermines judicial fairness. Third, the private nature of enjo-kōsai makes gathering evidence challenging. As a result, there have been instances of entrapment by law enforcement, which not only violates the ethical legitimacy of the law but also poses risks to the rule of law.

There are three main problems with the legal regulation of enjo-kōsai in Japan that require reflection. First, the construction of the "victim" narrative lacks agency, restricting the sexual autonomy of minors and framing them solely as victims, disregarding their agency. Second, there is insufficient justification for the criminalization of enjo-kōsai, as it is debatable whether eliminating all external influences can truly achieve the best interests of children. Third, the labeling of minors as "delinquent youth" hinders the protection of their legal interests. Placing them in detention or educational facilities and labeling them with a "sexual misconduct" tag may cause further harm.Similar issues regarding underage enjo-kōsai also exist in our country. Reflecting on the problems with the legal regulation of enjo-kōsai in Japan, we can draw the following three insights: First, we should respect and protect the sexual rights of children and clarify the legal nature of enjo-kōsai. Second, the criminalization of enjo-kōsai should be approached cautiously, focusing on prevention and improving social security and assistance mechanisms. This includes helping underage individuals involved in enjo-kōsai reintegrate into society and avoiding their involvement in professional prostitution. Third, we must be wary of the labeling effect on wayward youth to prevent labeled minors from experiencing educational and employment setbacks. Establishing specialized organizations for the protection of minors' rights, ensuring their rights to education and employment, providing strong psychological guidance, and ensuring fair treatment are crucial for their reintegration into normal life.